ED 056 492

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INSTITUTIONREPORT NOPUB DATEMOTE

EDRS PRICEDESCRIPTORS

ABSTRACT

DOCUMENT RESUME

009 348

Federico, Pat-AnthonvEvaluating an Experimental Au ,.o-Visual ModuleProgrammed to Teach a Basic Anatomical andPhysiological System.Air Force Human Resources Lab. Lowry AFB, Colo.AFHRL-TR-71-37Jul 7134p.

MF-$0.65 HC-$ 29*Audiovisw.A Instruction; *Comparative Analysis;Medical Education; Military Training; *ProgIamedInstruction; Student Attitudes

The learning pfficiency and effectiveness of teachingan anatomical and physiological system to Air Force enlisted traineesutili7ing an experimental audiovisual programed module was comparedto that of a commercial linear progr7:med text. It was demonstratedthat the audiovisual programed approach to training was moreefficient than and equally as effective as the programed textapproach to training. It was determined that trainees of differentlearning abilities acquired ds much knowledge about the digestivesystem from viewing the 20-minute audiovisual module as frominteracting for 80 to 120 minutes with the programed text. It wasestablished that students who differed in their mastery of therudiments of anatomy, physiology, and medical terminology performedequally well after audiovisual instruction or after writte programedinstruction. It was found that trainees reported more positivereactions to the audiovisual course than to the written program.(Author/JY)

AIR FOPC

F HR L-T R -71-37

EVALUATING AN EXPERIMENTAL AUDIO-VISUAL MODULEPROGRAMMED TO TEACH A BASIC ANATOMICAL AND

PHYSIOLOGICAL SYSTEM

By

Pat-Anthony Federico, Lt, USAF

Technical Training DivisionLowry Air Force Base, Colorado

July 1971

Approved for public ea-- distribution unli_

LABORATORY

AIR FORCE SYSTEMS COMMAND

BROOKS AIR FORCE BASIL TEXAS

NOTICE

When US Government drawings, specifications, or other data are used[or any purpose other than a definitely related Governmentprocurement operation, the Government thereby incurs noresponsibility nor any obligation whatsoever, and the fact that theGovernment may have formulated, furnished, or in any way suppliedthe said drawings, specifications, or other data is not to be regarded byimplication or otherwise, as in any manner licensing the holder or anyother person or corporation, or conveying any rights or permission tomanufacture, use, or sell any patented invention that may in any waybe related thereto.

AFHRL-TR-71-37

U.S. DEPARTMENT- OF HEALTH,EDUCATION & WELFAREOFFICE OF EDUCATION

THIS DOCUMENT HAS BEEN REPRO-DUCED EXACTLY AS RECEIVED FROM

THE PERSON OR ORGANIZATiON ORIG-INATING IT POINTS OF VIEW OR OPIN-

IONS STATED DO NOT NECESSARILY

REPRESENT OFFICIAL OFFICE OF EDU-

CATION POSITION OR POLICY

July 1971

EVALUATING AN EXPERIMENTAL AUDIO-VISUAL MODULE PROGRAMMED TO TEACHA BASIC ANATOMICAL AND PHYSIOLOGICAL SYSTEM

By

Pat-Anthony Federico, 1st Lt, USAF

Approved for public release; distri uttou unlimited.

TECKt"CAL TRAINING DIVISIONAIR FORCE HUMAN RESOURCES LABORATORY

AIR FORCE SYSTEMS COMMANDLowry Air Force Base, Colorado

FOREWORD

This study represents a portion of the in-house research program of Project 1121,Technical Training Development; Task 112101, Advanced Technology for Air ForceTechnical Training. Dr. Marty R. Rockway was the Project Scientist and Mr. Joseph Y.Yasut&ke was the Task Scientist. The report covers research performed between May1970 and September 1970.

The author wishes to express appreciation to Dr. Marty R. Rockway, Capt WayneS. Sellman, and Mr. Arnold L. Hanson of the Technica. fraining Division for reviewingthe manuscript. Special appreciation goes to TSgt Ozrow A. Ellis, Jr., Senior Instructor,Medical Service School, Sheppard AFB, Texas, for his extraordinary effort in preparingwid in recorcPng the script for the audio-visual instructional module; to Dr. Edgar A.Smith, Technical Training Division, for synchronizing the sound-slide presentation; and toSSgt Minor P. Johnson, Technical Trning Division, for photographing materials for thesupplementaiy slides. Also, the author would like to acknowledge the cooperation andassistance of Col William H. Behrens, Jr., Mr. William E. Baird, MSgt Edward W.Zwanziger, TSgt Raymond E. Ellis, SSgt Thomas E. Hutcheson, and AlC Michael E.Tillmans, all of the Medical Service School.

This technicp1 report has been reviewed and is approved.

George K. Patterson, ti olonel, USAFCommander

ABSTRACT

This study evaluated the learning efficiency and effectiveness of teaching ananatomical z -d physiological system to Air Force enlisted trainees utilizing anexperimental audio-visual programmed module and a commercial linear programmed text.It was demonstrated that the audio-visual programmed approach to training was more-fficient than and equally as effective as the programmed text approach Lcl training. 1 twas determined that trainees of different learning abilities acquired as much knowledgeabout the digestive system from viewing the 20-minute c.-J di °Nis u al module as frominteracting for 80 to 120 minutes with the programmed text. It was established thatstudents who differed in their mastery of the rudiments of anatomy, physiology, andmedical terminology performed equally well after audio-visual instructior or after writtenprogrammed instruction. It was found that trainees reported more positive reactions tothe audio-visual program than to the written program. It was recommended that withinthe Medical Service Fundamentals Course audio-visual progiammed instruction beemphasized and written linear programmed instruction be de-emphasized.

SUMMARY

Federico, P.A. Evaluating an experimental audio-visual module programmed to teach a basic anatomical andphysiologica! system AFHRL-TR-71-37. Lowry AFB Colorado: Technical Training Division, AirForce Human Resources Laboratory, July 1971.

Proble

Air Force enlisted medic0 and dental personnel begin their training with the Medical ServiceFundamentals Course at the Medical Service School (MSS), Sheppard Air Force Base, Texas. Included inthe core curriculum are units of instruction planned to teach rudiments of medical terminology, anatomy,and physiology. Currently, MSS is using a linear programmed text to teach these subjects which are neededas a basis for understanding structures and functions of major mechanical and chemical systems of thehuman body. Despite precautions taken by the author of this text, training managers at the MSS wereconcerned that some of their less literate trainees were havffig difficulty following the programmed text. Itwas thought that students were not given sufficient exposure to audio-visuals to enable them to viewsubject matter in an integrated way, or to understand its overall organization. The primary purpose o thisstudy was to determine whether a newly developed audio-visual programmed module was more effeAveand efficient than the currently used programmed text for teaching an instructional segment on thedigestive system in the course. A secondary purpose was to estimate student opinions and reactions to thisaudio-visual programmed approach of teaching this system, as opposed to the written progranimedap proach.

Approach

An audio-visual programmed module was developed to teach the rudiments of the digestive system. Itconsisted of synchronized 35mm color slides and an audio-visual tape; and it cov,:red the same enablingobjectives as the corresponding chapter from a linear programmed text. However, the script was not asredundant as the written programmed material. Air Force enlisted trainees had been randomly andpreviously placed into four classes; and educational media were randomly assigned to these classesaccording to a Solomon foui-group experimental design. Statistical comparisons of the groups were madein terms of posttest performance. Also, a theme analysis was conducted of student reactions and opinionstoward the audio-visual program and written program.

Results

It was demonstrated that the audio-visual programmed approach to training was more efficient thanand equally as effective as the programmed text approach. It was possible to reduce the duration of a lessonas much as 75 to 83 percent while still mejntaining its effectiveness by using a minimally redundantaudio-visual instructional module. Trainees of different intellectual abilities acquired as much knowledgeabout the digestive system from viewing the 20-minute audio-visual module as from interacting for 80 to120 minutes with the programmed text. Students who differed in their mastery of the rudnnerts ofanatomy, physiology, and medical terminology performed equaMy well after audio-visual instruction orafter written programmed instniction. Trainees Teported more positive reaction to the audio-visual programthan to the written program.

Conclusions

In view of the findings, it was recommended that within the Medical Service Fundamentals Coursethe utilization of audio-visual programs be maximized and the utilization of written programs beminimized.

This summary was prepared hy Pat-Anthony Federico, Technical Training Division, Air Fo ce HumanResources Laboratory.

Introduction

AB E OF CONTENTS

IL Method

Page1

2

SubjectsInstructional Media 3

Procedure

JIL Results ... . ...... ..... ............ 4

Effect of Media 4

Intellectual Abilities and Media = =5

Medical Rudiments and Media 5

Theme Analysis of Reactions Toward the Media

IV. Discussion

V. Conclusions and Recommendations _9

References 10

Appendix I. Script of the Audio-Visual Module Programmed to Teach theRudiments of the Digestive System .

Appendix II. Pretest

Appendix HI. Posttest

Appendix IV. Supple en Statistical Tables . . . . . . .. . . . .

LIST OF TABLES

3

17

21

23

TablePage

1 Means and Standard Deviations of Pretest and Posttest Scoresfor the Classes . . ........ .. 4

2 Analysis of Variance Table of Posttest Scores for the Factorial Analysisof Covariance, Stratified Variables: Pretest and Programmed Medium 5

3 Means, Adjusted Means, and Standard Errors of Posttest Scores for Pretested Classes 6

4 Means and Standaid Deviations of Posttest Scores for Gloups Classified Accordingto AFQT Scores and Programmed Medium . . . . 6

5 Analysis of Variance Table of Posttest Scores for the Factorial Analysis of Covariance,Stratified Variables: AFQT and Programmed Medium 6

Means and Standard Deviations of Posttest Scores for Groups Classified Accordingto Week-One knatomy and Physiology Test Scores and Programmed Medium . 6

7 Analysis of Variance Table of Posttest Scores for the Factorial Analysis of Covariance,Stratified Variables: Week-One knatomy and Physiolou Test and Programmed Medium 6

8 Means and Standard Deviations of Test Scores Available for Trainees 23

List of Tab e (Continued)

Table Page9 Correlation Matrix of Test Scores 23

10 Summary of the Wherty-Doolittle Method for Computing Multiple Correlation,Criterion Variable: Posttest

11 Regression Coefficients and Their Respective t Values for Tests ConcomitanPosttest Performance, Factors: Pretest and Programmed Medium 24

12 Regression Coefficients, Standard Errors, and t Values for the MultipleConcomitant Variables Used in the One-way Analysis of Covariana, Reported forTotal Source of Variation

13 Regression Coefficients and Their Respective t Values for Tests Concomitantto Posttest Performance, Factors: AFQT and Programmed Medium 25

14 Regression Coefficients and Their Respective t Values for Tests Concomitantto Posttest Performance, Factors: Week-One Anatomy and Physiology Test andProgrammed Medium

FIGURE

25

Figure Page1 Representation of the Solomon four-group experimental design adopted tor the study 3

EVALUATING AN EXPERIMENTAL AUDIO-VISUAL MODULE PROGRAMMED TO TEACHA BASIC ANATOMICAL AND PHYSIOLOGWAL SYSTEM

L INTRODULli

Air Force enlisted medical and dental personnelbegin their training with the Medical ServiceFundamentals Course, taught at the Medical Serv-ice School (MSS), Sheppard Air Force Base, Texas.Included in the core curriculum of this course areunits of instruction planned to teach therudiments of medical terminology, anatomy, andphysiology. Currently, MSS is using a linearprogrammed text to teach these subjects which areneeded as a basis for understanding the structuresand functions of the major mechanical andchemical systems of the human body. Despite theprecautions taken by the authors of this text(GPTC, 1964), there may be an exaggeration ofthe deficiencies of linear programs within thiscourse environment. Some of the inhe:-ent inade-quacies of written linear programs may be intensi-fied because of variability among trainees in theirintellecival abilities, aptitude levels, and readingskills. By using a very verbal programmed text toteach these students, the effectiveness of instruc-tion is extremely dependent upon the literacyskills of individual students. Consequently, train-ing managers at MSS were concerned that some oftheir less literate trainees were having difficultyfollowing the progammed text. One solutionsuggested to overcome this literacy problem was toteduce the requirement for reading skill throughthe use of a well-designed audio-visual instruc-tional program. Within the context of the currenttiaining program, it was thought that studentswere not given sufficient exposure to audio-visualsto enable them to view the subject matter in anintegrated way, or tc understand its overallorganization. It seemed likely, however, that anappropriate audio-visual module might provide aframe of reference which would make it easier forstudents to associate technical terms with theanatomical structures and physiological functionsthey signify.

There is considerable support within psycho-logical and educational literature for suggesting theuse of audio-visual media in this context. It hasbeen stated that there are several intrinsic insuffi-:eiencies in many written linear programs. Four-essential features characterize these plograms.Firstly, the subject matter is broken up into smallunits which are presented to the student in a linearfashion by successive frames. Secondly, after

answering the first question or filling in one ormere blanks in a statement a check-answer ispie.iented to the student within the same frame orwithin the next N,-..ntial frame where a new unitand question appear. Thirdly,, thiq procedure ismechanically repeated to the end of the prob=Fourthly, there is no provision for varying thelinear sequence except by repetition of a set offrames prior to proceeding to the next set. Forexample, Skinner (1954, 1958) prescribed thefollowing features for effective teaching programs:t7'e step-by-step procedure, the active constructedresponse required of the learner, the promptreinforcement of every responfe provided by thecheck-answer, and the self-pacing permitted by theprogram.

According to Smith and Smith (1966), one ofthe most serious deficiencies of Skinnerianprograms is the restricted nature of the materialthey present. That is, these progrunmed textsmake almost nci use of nonverbal dispiuys andother supplementary aids. Teaching a course by awritten linear program is deliberately limiting themedia of communication, the experiences of thestudent, and consequently, the range of under-standing he achieves. Sonic researchers andeducators (Pressey, 1963; Smith & "omith, 1966)believe that the most promistng approach totraining is to provide the student with a broadcontext of experience by resorting to the greatgamut of gadgets employed as communicativemedia. If learning consists of an association ofmany, different, multimedia stimuli and responses,then the fixed-sequence, constructed-response,arbitrarily simplified, bit-by-bit, linear frames of aSkinnerian programmed text are insufficient, andmay not even be necessary, for efficient and effec-tive learning.

Linear programming tends to emphasize thearticulation of material in terms of its detail. In sodoing, it constructs no general context. There arefew bodies of knowledge that do not lose somemeaning and significance if presented automat-ically as a series of discrete steps. It appears to bealmost impossible for a conventional Skinnerianprogram t o teach the broader aspects andmeanings of a subject, since programming stressesjuggling of verbal units, rather than integratingverbal presentations with visual displays, demon-strations, and direct experiences.

According to Pre,sey (1963), new instructionalmaterial should not be initially presented to atrainee in a bit-by-bit fashioii in a programmedtext, but rather in a larger, more meaningfulwhole. For the first go-through or the final review,discrete programs are unsatisfactory. One of themost important aspects of new material to belearned is its structure. Detailed programmingdestroys most of this except the serial order.Similarly, Smith and Smith (1966) stated:

A Skinnerian progam makes no provision formanipulating the material in flexible ways todiscover unusual relationships and varied meanings.When linear, small-step programs are used, thelearner's performance may take on the character-tics of a vigilance task, in which restrictivesensomotor conditions prevent effective feedbackcontrol. Such progams reduce the possibifities forindividua&ed control over the learning situationby riOdly restrictnig the activities of the learner toa series of discrete responses. Such monotonousdesign can be justified only for practice on discreteunitary items, such as spelling words, and then notfor too long a period..

Inasmuch as linear progams are thought bySkinnerians to be analogous to an operant condi-tioning sequence, no thought is given to theirspatlal reference systems. The questions andarswers compose a temporal series of discreteunits, and few, if any, organized perceptu0displays are given the student to help him under-stand the over-all organization of the subjectmatter. Thus for material that has inherent logicalstructure, a linear program is a poor teacher.Audio-visual teaching machines have some advan-tages over rest.-icted verbal programs in that theycan display graphs and illustrations to give spatialreference to the verbal material (p.295).

Audio-visuals, textbooks, demonstrations,experiments, lectures, and other diversifiedpresentations aid tn establishing a frame of refer-ence against which new material can be embedded,thus enhancing its meaning. Paradoxically, wfitersof progarnmed texts eliminate from frames as"extraneous" material which should often beincluded in order to provide as rich a context aspossible. Presenting a new subject in diverse, inter-esting ways increases the transfer potentia of thelearned matenal. One way to insure the transfer-ability of what has recently been acquired is tovary the conditions of learning. An attempt ismade to do this in programmed texts by includinggeneral rules and examples, and by endeavoring tovary the wording in frames. However, theseprograms are still very restricted when comparedwith the many different aural and visual, verbalarid nonverbal techniques of the classroom.

Several researchers (Briggs & Naylor, 1962;Kendler, 1959; Krumbeltz & Weisman, 1962;Nunn, 1961) have suggested that limited linearprograms teach equally limited knowledge. Theyimplied that to teach a rigid system of specificresponses, a written linear program may do thejob. But to educate in a broader sense, a variety ofmedia, a diverse approach, and a potential forflexible responses on the part of th- learner are themandatory minimum. Only id thcse ways can thestudent's frame of reference be varied enough toassist in the transfer of what has been learned tohelp solve newly encountered problems. Generally,it has been concluded that graphic-verbal means ofcommunication are better than verbal alone; it hasbeen demonstrated that films, sound-slide pro-grams, and other audio-visual devices are equiva-lent to an average teacher in some cases (Smith &Smith, 1966). It should be emphasized that thesefindings have not been established universally, forthere are very many variables in audio-visualmaterials, in the students, and iP the teaching-respondnig situations, to name only a few, thateffect the learning that occurs. The primarypurpose of the present study was to determinewhether a newly developed audio-visual program-med module was more effective and efficient thanthe currently used programmed text for teachingan instructional segment on the digestive system inthe Medical Service Fundamentals Course atSheppard Air Force Base. A secondary purposewas to estimate student opinions and reactions tothis audio-visual programmed approach of teachingthis system, as opposed to the writtenprogrammed approach.

II. METHOD

Subjects

The subjects were 112 Air Force enlistedtrainees enrolled in the Medical Service Funda-mentals Course, 3AQR90010, at Sheppard AirForce Base, Texas. These subjects were randomlyassigned to one of four classes designated Class In = 25), Class 2 21), Class 3 = 24), andClass 4 (n = 42), respectively. Several test scoreswere available for each of the subjects: ArmedForces Qualification Test (AFQT); Airmen Quaid-ing Examination: General (AQE Gen), Administra-tive (AQE Admin), Electrical (AQE Elec), andMechanical (AQE Mech); Quickword Test (Quick-w ord), .a short intelligence test (Borgatta &

10

Corthii, 1964); and Week-one Anatomy andPhysiology Test 011k-1 Anat&Phys). This lattertest (Wk-1 Ariat&Phys) is given at the completionof the first week of the Medical Service Funda-mentals Course; it was written by the instructorsat MSS to test these enabling objectives: elemen-tary medical terminology, ariatomy, and physi-ology.

Instructional Media

The instructional media employed in this studywere a commercially developed Skinnerianprogrammed text and an experimental audio-visualprogrammed module. Specifically, the writtenprogrunmed material consisted of 38 pages fromChapter 7, The Digestive System, The HumanBody and Its Function: A Programmed course,(GPTC , 1964); the audio-visual programmedmaterial consisted of synchronized 35mm colorslides and an audio tape. The slide projector usedwas a Kodak Carousel, Model 850; the reel tapeplayer-recorder used was a Roberts sound-with-sound model 1650. The pulses to automaticallychange slides were placed on the audio tape with aKodak Carousel Sound Synchronizer, Model 2. Ofthe 25 slides, approximately three-quarters wereobtained from the CIBA Collection of ProjectionSlides of Medical Illustrations by Frank H. Netter,MD. (These slides, and others, were made availableat no charge for this study by the CIBA Pharama-ceutical Company, Summit, New Jersey.) Thecontents of other slides in the series were drawnby professional illustrators. Also, these additionalillustrations were photographed, developed, andmounted as 35mm projection slides by photo-graphic personnel of the Air Force HumanResources Laboratory. The script for the audiotrack was written, read, and recorded by TSgtOzrow A. Ellis, Jr. of the MSS; it covered the sameenabling objectives as the programmed chapter.However, the script (see Appendix 1) was not asredundant as the written programmed material. Aneffort was made to stimulate active student partic-ipation in this audio-visual module. Tlus wasattempted by requiring trainees to respond overtlyto questions asked on the audio tape regarding thecontents of specific slides. Prticipation requiredof the trainees was induced in order to somewhatmatch the participation demanded of the studentsby the programmed chapter.

Procedure

All four classes began the Medical ServiceFundamentals Course using only the progarnmed

. 1. Reprewntation of the Solomon four-groupexperimental design adopted for the study.

Class

Treatment

PretestProgrammed

Medi:3m Posttest

X Audio-visualX Written text

Audio-visualWritten text

text. They had completed the tint six chapters ofthis text covering sequentially the Organization ofthe Human Body, the Skeletal System, theMuscular System, the Nervous System, theCirculatory System, and the Respiratory System.Completion of this material required response toeach of the first 99 pages of the programmed text.All of the students had finished this task in theseven hours of classroom time allotted. Thetrainees responded to the written program for twohours in the afternoon of the first day of thecourse; they received a 10-minute break betweenthese classroom hours. Most of the second day wasdevoted to following the text. This resulted inapproximately five hours of interacting with theprogammed text since one-sixth of daily sched-uled classroom time was set aside for studentbreaks. Each of the four classroom instructors wasrequested not to assist his surdents, or make anycomments to them about the subject matterduring this time.

This study was conducted during most of themorning of the third day of the course. It involvedrandomly assigning the educational media toclasses according to a Solomon four-group experi-mental design. The advantages derived fromemploying this experimental scheme have beendiscussed by Cambell and Stanley (1963). Thespecific assignment of the different media, thepretest, and the posttest to the classes is depictedin Figure 1. The pretest given to two classesrandomly selected, and the posttest given to oEfour of the classes, are presented in Appendixes IIand III, respectively. These tests which measuredcourse enabling objectives were -scored byawarding one point for each correct answer; thus,the highest scores possible were 50 and 25 for thepretest and posttest, respectively. Class 2, thepretest-posttest control group, was initially given apop-quiz at 0800 covering the first seven chaptersof the programmed test. They were allowed 60minutes to complete this test, fifty percent of

which dealt exclusively with the digestive system.Following a 20-minute break, they were instructedto complete Chapter 7, the Digestive System, andto be prepared for a test on the material immedi-ately following the task. Subsequent to theinstructions, the trainees began responding to thisprogram; all trainees covered the chapter within 80to 120 minutes. The instructor administered theposttest to each student within 3 minutes after hefinished responding to the program, allowing 30minutes to complete the posttest. Upon conclu-

i of this task, students were requested to make.ritten comments, during the next 15 minutes,

expressing their own opinions and reactionstoward using a programmed text to learn anatomy,physiology, and medical terminolou of the diges-tive system. Class 4, the posttest-only controlgroup, was not given the pretest covering the firstseven chapters of the programmed text. Otherwise,they followed the same procedure as Class 2,beginning with Chapter 7 at 0900. Class I, thepretest-posttest experimental group, followedessentially the same procedure as Class 2.However, they covered the digestive systemmaterial by viewing, as a group, the sound-slideprogram. The duration of this audio-visual instruc-tion was 20 minutes. The time intervals betweenthe pretest and the sound-slide progam, and thesound-slide program and the posttest, were thesame as those for Class 2. ANo, this class wasrequested to make written comments expressingtheir own opinions and reactions toward observingthe audio-visual programmed module to learn theanatomy, physiology, and medical terminology ofthe digestive system. Class 3, the posttest-onlyexperlinental group, followed essentially the sameprocedure as Class 4. However, they covered thedigestive system material viewing, as a group, theaudio-visual program. The four instructorsmoratored their respective classes throughout thesound-slide showing or the programmed chapterresponding. They were instructed not to make anycomments about the digestive system to theirstudents while, or immediately after, they viewedor interacted with the materiO.

IIL RESULTS

Effect of Media

The means and standard deviations of testscores for the sample of enlisted medical traineesare presented in Appendix IV, Table 8; the inter-correlation matrix of these test scores is given inAppendix IV, Table 9. A summary of the Wherry-

4

Table 1. Means and Standard Deviations of Pretestand Posttest Scores for the °asses

Pretest Posttest

Class Mean SD Mean SD

1

234

25212442

32.439933.7500

5.35765.6480

19.520020.857119.666618.9286

3.26762.15143.26603.8279

Doolittle Method for computing multiple co ela-tion (Guilford, 1965), using the posttest as acriterion variable, is presented in Appendix IV,Table 10. Note that for this entire sample of 112students, the optimum concomitant variables ofhi-class performance as measured by the criterionwere Wk-1 Anat&Phys, Quickword, AQE Gen,AFQT, and AQE Mech, respectively. This multipleregression analysis was computed primarily todetermine the best covariates of the criierionamong all the test scores available for thesetrainees.

In Table 1 are the means and standard devia-tions of pretest scores for Classes 1 and 2, and theposttest scores for Classes 1 through 4. Using ascovariates those test scores which were found bythe multiple regression analysis to be concomitantto posttest performance, a two-by-two factorialanalysis of covariance was calculated for thecriterion scores. One factor was defined as pre-testing, its occurrence or nonoccurrence forclasses; the other factor was defined as pro-grammed media, audio-visual or text. Theregression coefficients of tests found to covarywith posttest performance and their respective tvalues are thown in AppendLx IV, Table 11. Asummary of the analysis of variance of posttestscores for this factorial analysis of covariance isexhibited in Table 2. Note that neither the maineffect of pretesting nor its interaction was foundto be significant. It can be concluded, then, thatthe pretest was not reactive in terms of sensitizingClasses 1 and 2 to the material that was to becovered on the posttest. Consequently, the resultsob tained for the pretested classes could beconsidered as representative of the effects of theexperimental factor, media, for the unpretestedclasses as well.

Since this generalization was possible (due tothe findLngs of the preceding factorW analysis ofcovariance), a one-way analysis of covariance, withmedia the criterion of classification, was computedusing the scores of students in the pretested

Table 2. Analysis of Variance Table of PosttestScores for the Factorial Analysis

of Covariance, Stratified Variables:Pre test and Programmed Mediwn

St,urce ofVariation F*

Pretest (P) 1 5.8513 .8749Programmed Medium (M 1 22.4924 3.3630P x M 1 .6789 1015Residual 75 6.6882

Note. Covariates used in this analysis are those con-comitant variables presented in Appendix IV, Table 11.Acquisition time was not used as a covariate in this ana-lysis and other reported relevant analyses since thismeasure was affected by the experimental treatments.Had any of the F ratios been significant, it would nothave been possible to conclude validly that the experi-mental treatments had differential effects (Lindquist,1956).

413

classes, Classes 1 and 2, only. Multiple covariates,including pretest scores, were used in this analysis.These covariates together with their regressioncoefficients, standard errors, and t values are givenin Appendix IV, Table 12. The one-way analys!s ofcovariance indicated that there were no sigrificantdifferences among class-posttest scores afteradjusting with those covariates reported inAppendix IV, Table 12. The means, adjustedmeans, and standard errors of the posttest scoresfor pretested Classes I and 2 are presented inTable 3. It can be concluded then that the20-minute audio-visual programmed moduletaught the digestive system equally as well as thechapter from the programmed text which tookstudents anywhere from 80 to 120 minutes tocomplete. Needless to say, a very substantial savingwas realized by bringing Class 1, in approximatelyone-fourth to one-sixth the time, to a plateau ofperformance which did not differ from that ofClass 2. These results showed that it was possible,by -using a minimally redundant andio-visualinstructional module, to reduce the duration of alesson by as much as 75 percent to 83 percent,while still maintaining its effectiveness.

Intellectual Abilities and Media

Subjects were also sorted into high and lowAFQT groups according to whether or not theirscores were above or below the median on this testfor this specific sample, 62.5. Subsequently,within each of these AFQT groups, subjects were

5

divided into audio-visual and written textsubgroups, according to the programmed mediathey received. This classification scheme resultedin four other goups from which trainees wererandomly discarded in order to produce an equalnumber of subjects per group (n 20). The meansand standard deviations of the posttest scores forthese groups are shown in Table 4. Regressioncoefficients and their respective t values for testsconcomitant to the posttest performance of thefour groups are given in Appendix IV, Table 13.Using as covaliates those tests tabulated inAppendix IV, Table 13, a two-by-two factorialanalysis of covariance was computed for posttestscores. One of these factors was defined as AFQT,high versus low; the other factor was defined asprogrammed media, audio-visual versus text. Asummary of the analysis of variance of posttestscores for the factorial analysis of covariance ispresented in Table 5. As can be seen, neither themain effect nor the interaction source of variationwas found to be significant. Postulating thatpretest equivalence of these four groups ofsubjects was approximated by randomization,additional information was obtained, from theresults of this analysis, regarding the performanceof trainees on the posttest. Namely, the high andlow AFQT groups did not differ in their levels ofachievement. Further, the high and low AFQTsubgroups which viewed the audio-visual programdid not differ in their degree of att&mment fromthe high and low AFQT subgroups whichiesponded to the written program. Trainees then,who differed somewhat in their basic intellectualabilities (verbd, numerical, spatial, or mechanical)as measured by the AFQT, learned as much aboutthe digestive system from the avdk)-visualprogammed module as from the programmedtext.

Medical Rudiments and Media

Trainees were further categorized into high andlow Wk-1 Anat&Phys groups accolding to whetheror not their scores were above or below themedian on this test for this sample, 47.5. Withineach of these Wk-1 Anat&Phys groups, su;)juelswere sorted into audio-visual and text subgroupsaccording to the progrwrimed media they received.This classification scheme produced four newgroups from which trainees were randomlydiscarded in order to form an equal number ofsubjects per group (n 23). The means andstandard deviations of posttest scores for thesegroups are tabulated in Table 6. Regressioncoefficients and their v,sociated t values for tests

Table 3. Means, Adjusted Means, and StandardErrors of Posttest Scores for Pretested Classes

ClassClassMean

AdjustedMean

SEAdjusted

1 19.5200 19.5650 4.81252 20.8571 20.7939 5.4216

Note.-A one-way analysis of covariance with multiplecovariates, includirg pretest scores, indicated that therewere no significant differencc:s among class posttest scoresafter adjusting with those covariates reported in Table 5(Adjusted MS between Classes = 1462.7539; F(1, 38) =2.6910; p > .01).

Table 4. Means and Stamfard Deviationsof Posttest Scores for Groups Classified

According to AFQT Scores andProgrammed Medium

(n = 20)

AFQT Audio-visualGroup Mcaii

Written textSD Mean SD

High 20.8999 2.6137 19.7000 2.9037Low 18.0499 3.0344 18.7999 4.0471

Note.-Subjects were classified into high and low scor-ing groups according to their scores on the AFQT relativeto the medimi for this sample, 62.5.

Table 5. Analysis of Variance Table of PosttestScores for the FactoriW Analysis

of Covaiiance, Stratified Variables:AFQT and Programmed Medium

Source ofVariation df MS

Programmed Medium (M) 1 6.6223 .8634AFQT (Q) 1 .0559 .0073MxQ 1 27.7048 3.6121Residual 73 7.6670

Note.-Covariates used in this analysispresented in Appendix IV, Table 13.

*p > .01.

are those

concomitant to posttest performance of these fourgroups are presented in Appendix IV, Table 14.Using as covariates those tests reported inAppendix IV, Table 14, another two-by-two fac-torial analysis of covariance was calculated forposttest scores. One of these factors was specifiedas Wk-1 Anat&Phys, high versus low; the otherfactor was specified as programmed media, audio-visual versus text. A summary of the analysis ofvariance of posttest scores for this factorial

6

Table 6. Means and Standard Deviationsof Posttest Scores for Groups Classified

According o W-2ek-One Anatomyand Physiology Test Scores and

Programmed Medium(n = 23)

Wk-1Anat&Phys

Group

Audio-visual Written text

Mean SD Mean SD

High 20.9130 2.9987 21.0869 2.6097Low 18.1739 3.0697 18.3478 3.2278

Note.-Subjects were classified into high and lowscoring groups according to thefr scores on the Week-OneAnatomy and Physiolou Test relative to the median forthis sample, 47.5.

Table 7. Analysis of Variance Table of PosttestScores for the Factorial Analysis of Covariance,Stratified Variables: Week-One Anatomy and

Physiology Test and Pr -mmed Med:um

Source ofVariation df MS

Wk-1 Anat&Phys (W) 1 29.0085 3.6584Programmed Medium (M) 1 6.0872 .7677W x M 1 .0027 .0003Residual 85 7.9293

Nc .-Covariates used in this analysis are.2c1 in Appendix IV, Table 14.

*p > .01.

analysis of covariance is given in Table 7. In thistable, too, i can be seen that neither the maineffect nor the interaction source of variation wassignificant. Again assuming that pretest equiva-lence of these four groups of subjects was approxi-mated by randomization, the analysis producedfurther information concerning the trainees'posttest performance. It hidicated that high andlow Wk-1 Anat&Phys groups did not differsignificantly in then- postiest scores. Also, the highand low Wk-1 Anat&Phys subgroups whichreceived the audio-visual module did not differ intheir level of achievement from tilt high and lowWk-1 Anat&Phys subgroups which received theprogrammed text. It can be stated that studentswho differed to some extent in their mastely ofthe rudiments of anatomy, physiology, andmedical terminology, as measured by the Wk-1Anat&Phys test, demonstrated as much knowledgeabout the digestive system after seeing the sound-slide program as after responding to the writtenprbgram.

14

Theme Analysis of ReactionsToward the Media

Analysis of student reactions and opinionstoward the audio-visual program and the writtenprogram, expressed in their critiques, revealedseveral predominant themes. On the positive side,trainees expressed that they liked watching theaudio-visual programmed module better thanfollowing the programmed text. This was sobecause, in their opinion, the wiitten program wasrepetitious and redundant. That is, by using thetext they had to keep reading the same materialover and over again. The students lound this verymonotonous and tedious; whereas, they felt thatthe audio-visual instruction went directly to thepoint of what should be learned. Consequently,the trainees thought that the sound-slide programhelped them to acquire the material more easily.Mso, they asserted that this kind of instmctionkeeps the class interesting, thus enhancing theirattention, because they could see what was insidethe human body. They noted that the subjectmatter was easier to understand when one canactually view in color what specific anatomicalstructures look like. This attitude is expressed inthe following quote from a student's critique:

I found this (the audio-visual module) to bevery interesting over the book (the programmedtext). I would suggest that this be used, with theidea of the student being able to see and hearcloser to life examples, to place and rememberitems better.

On the negative side, a majority of studentsthought that the pace of the audio.visual modulewas too rapid. However, many claimed that theystill managed to gasp the material because thespeed of the presentation increased their attentive-ness. Some students expressed the view that toomany medical terms appeared on the slides, thusincreasing their complexity. This may have inter-fered with their efforts to associate an anatomicalstrncture with its corresponding nomenclature,Also, a few trainees expressed their concern overnot being able to ask any questions during thesound-slide program; but they acknowledged thatthis is also true when they responded to thewritten program. In summary, practically astudents had more favorable attitudes toward theaudio-visug programmed module than toward theprogrammed text It should be noted here thatstudent attitudes toward programmed materialsmay bear little relation to the teaching effective-ness of Lhose materials (Eigen, 1963; Hough &Revoir, 1963; Vernon, 1953).

7

IV_ DISCUSSION

The findings of this study support the conclu-sions of many previous investigations and substan-tiate several psychological theories of training.S tating this rather conservatively, some pro-grammed texts use some repetidon of words,phrases, and principles. Also, some of these booksrequire learners to repeat programs until they haveachieved mastery. The results of this and otherinvestigations (Valverde & Morgan, 1968) suggestthat such repetition hardly seems necessary. Forexample, Valverde and Morgan found that byeliminating the usual redundancy in a linearprogammed text on medical terminology, equiv.a-lent achievement was attained by Air Forceenlisted trainees using a minimally redundantlinear program, a brief narrative of the sameinformation, and a study card which presentedessential medical prefixes, suffixes, and stems.They concluded that excessive programmedpractice may detract from the effectiveness of aself-instructional program. In mars/ cases leanprograms seemed to be more economical andefficient than programs which containedredundant material. Whether these effects wereproduced by the nature of the instructionalmaterial itself, or by the iisteraction between theinstructional material and motivational factors, isdifficult to interpret. However, considering thestudent reacions in this study, the motivationgaspect appears lo be a significant factor inaccounting for the effectiveness of theexperimental audio-visual module. Motivation isalso given primary .importance in McDonald's(19 61) theoretical analysis of audio-visualprogrammed rnaterals. He did not deny thataudio-visuals might seri, as specific instructionaltools; but he attached more importance to theirmotivating value in arousing the interest ofgtudents, and in directing their attention to themore salient aspects of a subject. McDonald alsostressed the importance of using audio-visualsproperly to create learning sets or to orient thestvdent in the right direction.

The results of this investigation can be inter-preted from another point of view. Most Skin-nerian programmers believe that linear, stepsshould be giadual enough so that errors inresponding rarely occur. Galanter (1959) suggestedthat the error rate should be below ten percent.Using easy programmed texts made up of verysmall steps, like the chapter on the digestivesystem, has revealed what Rigney and Fry (1961)

have called the "pail effect": the boredom inducedby such material, especially in bright students.According to the contents of the student critiques,this effect manifested itself in this study, Severalcharacteristics of linear programs, stated Rigneyand Fry, contribute to their implicit tedium. Mostobvious is the repetition that is deemed necessaryto teach material in this fashion. Apparently,practically all analyses of Skinnerian programmingstress the importance of repetition. A typicalcomment was the one made by Smith (1959): "Ifthere are several ways to say the same thing, usethem all. Redundancy is required." A secondcharact -f -ir! of written linear programs, remarkedRigney and Fry, that make them seem dull andlifeless is the deliberate simplicity of each frame.Progra:rmers proceed on the assumption that anyportion of an item which is not necessary for thestudent to arrive at the correct answer should bedeleted. Smith asserted, "Eliminate all irrele-vancies except contrived anticipators." Framesdesigned in this manner may lead the learnerdirectly to the response desired by the program-mer, but they do little to stimulate to earner'sinterest in the larger aspects of the subject matter.A third deadening feature of Skinnerian programs,according to Rigney and Fry, is the contrivedartificiality of their structure. Air Force trainees,for example, attempting to get some under-standing of a complex subject matter deserve morethan the verbal and mechanical artifices of atypical linear program. The tiny bits ofinformation doled out in discrete steps, the verbaland grammatical tricks, the mechanical prompts allseem calculated more to frustrate students than toenlighten them. These techniques, along with theother devices that structure a written linearprogram, tend rather to obscure meaningful inter-relationships than to clarify them. As affirmed byRigney and Fry, "It is a very real danger that thestudent plodding through a linear program will notbe able to see the forest for the trees."

The results of this research can be seen fromanother perspective which is implied by theimmediately preceding comments. Skinnerianoperant conditioning principles and methods, thatappear to work so successfully in training animals,are assumed to apply to human learning as well.The assurance with which the Skinnerian theoristsapply their animal training techniques to thecomplexities of human behavior was illustrated byHolland (1960): "This principle of gradu0progression runs through many of the teachingmachine techniques. But human and avian scholaisdeserve the same careful tutorage." This Skin-

nerian programmed approach proposed to revolu-tionize education by leading learners through acarefully arranged series of small steps fromignorance to mastery, while they seldom if everencounter failure. According to Smith and Smith(1966), if one endeavors to weigh Skinnerianconcepts on their psychological merits, onediscovers firstly

....there are obvious thuigs to be said about thepeon analogy. People are not pigeons. They donot . . . except under certain restrictedcircumstanceslearn hle pigeons. [Secondly], thecomplex sequence ... used to shape the behaviorof a laboratory pigeon has no inherent structureand organization except in the thirLking of theexperimenter and ... thus has no adaptive func-tion for the pigeon that learned it except under theartificial and arbitrry arrangements of the operantcondifioning laboratory. In contrast, the sort ofbehavior taught to human students in school ismeaningful to people in general, serves adaptivepurposes in a variety of situations in school andout, and is subject to confirmation and correctionby the way it falls into place within the larger areaof human knowledge and experience (p. 289).

It does not seem likely that the principles oflearning which describe the behavior of animals inlaboratories can be extrapolated to humans intraining environments. Then again, a resourcefulteacher probably m...ver learned his communicativeskills in an animal laboratory (Quinn, 1963). Alinear programmed text tends to focus its atten-tion exclusively on the articulation of material interms of the amount of detail. In so doing, itestablishes no general context or frame of refer-ence. Some of the meaning and significance of asubject cannot help but be lost due to its beingmechanically presented in a series of discrete steps.Consequently, it would appear to be almostimpossible for a linear written program to teachtrainees the broader aspects of anatomy andphysiology.

Needless to say, the teaching effectiveness ofSkinnerian programmed texts was questioned bythis study; it was also doubted by Homme andGlaser (1960). They reported instances in theirexperimental work on programmed materials whenthe correct answers were inadvertently omitted.Much to their surprise, the subjects sometimesinsisted that the omission made no difference. Tothese learners, extrinsic confirmation of correct-ness was not always necessary. Also, no externalreinforcement was precisely contingent upon theirresponses; yet, they learned the materials. Theimplications of this, expounded Homme andGlaser, are that no one had pinned down the exactnature of the reinforcement in self-instruction, and

that at times subjects had learned even withoutspecific reinforcements. As evidenced by the AirForce medical trainees used in this of, studentsare often too impatient to wait around to havetheir behavior shaped bit by bit. A learner whounderstands the material well often resents theslow pace imposed by this procedure. This isespecially tnie if the new subject matter is mean-ingful and fits well into their present frame ofreference.

It seems that Skinnerian programs are tooinflexible to do justice to human capabilities inlearning. Written linear programming tendsnaturally toward an educational regimentationthat does not make adequate allowances for thedifferences that exist among learners, among theirteachers, and among the subjects to be tar:tt. Nordoes a linear programmed text take ad antage ofthe many channels of communication -fiat can beused in instruction (Smith & Smith. 1966). Bydictating the same sequence of responses for alllearners, a program that serves the needs of arelatively dull or uninformed individual becomes adrag on a learner who is better equipped Accord-ing to Smith and Smith, Skinnerian programme:shave made much of what they call self-paced in-struction. In reality, however, writing out manydiscrete responses makes it impossible for brightstudents to move ahead at a rate commensuratewith their ability. It should be emphasized thatnot only do programmed texts fail to make allow-ances for individual differences among students,but also they provide a very poor medium forexpressing individual differences among instruc-tors. The programmer now becomes the voice ofauthority and shapes the behavior of the learneralong prescnbed pathways. As Jordan (1963)stated, Skinnerian programs by no means teach bythe Socratic method, but are completelyauthoritative.

V. CONCLUSIONS AND RECOMMENDATIONS

1. This study demonstrated thaf the 20-minute minimally redundant audio-visual progarnwas as effective as the written program, whichrequfred anywhere from 80 to 120 minutes tocomplete, for teaching Air Force enlisted medicaltrainees the rudiments of the digestive system.Thus, a substantial reduction was realized in theamount of training time needed to bring studentsto levels of acidevement which did not differ.

2. This investigation indicated that AFQTsubgroups defined on the basis of high and low

17 9

scores did not differ in their level of performancemeasured by the posttest. It found that high andlow AFQT students who observed the audio-visualmodule did not differ in their degree of attainmenttrom the high and low AFQT students whocomplete the programmed chapter. It wasconcluded Laat trainees who differed somewhat intheir basic abilities to leam as measured by theAFQT acquired as rneny facts about the digestivesystem from watching the audio-visual progr, m asfrom interacting with the written program.

3. This researn determined that the subgroupsdefined on the basis of high and low Wk-1Anat&Phys scores did not differ in their postte!aperformance. Furthermore, it dernonstiati'd thathigh and low Wk-1 Anat&Phys subjects who hadseen the audio-visual module did not differ in theirlevel of achievement from the high and low Wk-1Anat&Phys subjects who had responded to theprogrammed text. It was deduced that traineeswho differed somewhat in their mastery of therudiments of anatomy, physiolou, and medic0terminology, as measured by the Wk-1 Anat&Phystest, manifested as much knowledge about thedigestive system after the audio-visual instructionas they did after the written programmedinstruction.

4. From the sampled student reactions andopinions toward the audio-visual and the writtenlinear progams for teaching the digestive system,it was revealed that medical trainees liked viewingthe audio-visual program better than using thewritten progam. This was so, students claLined,because the text was very monotonous andtedious. Pdso, the trainees asserted that the audio-visual module went directly to the point of whatshould be learned, and that it was more interestingthan the programmed text. Consequently, theaudio-visual programmed instruction helped themto attend to and to retain the material more easilythan the written programmed instruction.Negatively, many trainees thought that the pace ofthe audio-visual module was too rapid. Somestudents expressed concern over the complexity ofsome of the slides, and over not being able to askany questions during the sound-slide showing.Most students, however, had more favorableattitudes toward the audio-visual module thantoward the programmed text.

5. In light of the findings, it was recommendedthat utilization of audio-visual programs bemaximized and utilization of written programs beminimized within the Medical ServiceFundamentals Course.

REFERENCES

Borgatta, E.F., & Corsini, RN. Quickword testmanual, New York: Harcourt, Brace and World,1964.

Briggs, C.E., & Naylor, V.C. The relative efficiencyof general training methods as a function oftransfer task complexity. Journal of Experi-mental Psychology, 1962, 64, 505-512.

ampell, D.T., & S aniey, J.C. Experimental andqua si-experifuental designs for research onteaching. in N.L. Gage (Ed.), Handbook of re-search on teaching Chicago: Rand McNally,1963.

Deese, J. Comment and summary: A mine ofpossible applications. Audio-Visual Communi-cations Research, 1961, 9 (5), 79-87.

Eigen, L.D. Hi i-school student reactions to pro-grammed instruction. Phi Della Kappan, 1964,44, 282-285.

Gatanter, E. The ideal teacher. In E. Galanter(Ed.), Automatic teaching: The state of the art.New York: Wiley, 1959.

General Programmed Teaching Corporation(GPTC). The human body and its functions: Aprogrammed course. Chicago: EncyclopediaBritannica Press, 1964.

Guilford, J.P. Fundamental statistics in psycho-logy and education. New York: McGraw-Hill,1965.

Holland, J.G. Teaching machines: An applicationof principles from the laboratory. In A.A.liumsdaine and R. Glaser (Eds.), Teachingmachines and programmed learning; A sourcebook. Washington, D.C.: National EducationAssociation, 1960.

Homme, L., & Glaser, R. Problems in programmingverbal learning sequences. In A.A.Lumsdaineand R. Glaser (Eds.), Teaching nzachines andprogrammed learning; A source book.Washington, D.C.- National Education Associa-tion, 1960.

Hough, J.B., & Revoir, B. Programmed instructionat the college level: A study of several factorsinfluencing learning. Phi Della Kappan, 1963,44, 286-291.

Jordan, J.A. Socratic teaching. Harvard i7:luca-ticmal Review, 1963, 33, 96-104.

Kendler, H.H. Teaching machines and psycho-logica' theory. In E. Galanter (Ed.), Automaticteaching: The state of the art. New York:Wiley, 1959.

Kendler, H.H. Stimulus-response psychology andaudio-visual education. Audio-visual Communi-cations Review, 1969, 9 (5), 33-41.

Krumboltz, J.D., & Weisman, J.G. The effect ofovert vs. covert responding to programmedinstruction on immediate delayed retention.Journal of Education Psychology, 1962, 5389-92.

Lindquist, E.F. Design and analysis of experimentsin psychology and education. Boston:Houghton Mifflin, 1956.

McDonald, T.J. Motivation and the communica-tion processes. Audio-visual communicationsReview, 1961, 9 (5), 57-67.

Nunn, G. An English teacher looks at programmedlearning. Audio-visual Instruction, 1961, 6,1411 42.

Pressey, S.L. Teaching machine (and learningtheory) crisis. Journal of Applied Psychology,1963, 47, 1-6.

Quinn, A.K. How to program (in 10 difficultlessons). Audio-visual Instruction, 1963,80-83.

Rigney, J., & Fry, E. Current teaching-machineprogram and programming techniques. Audio-visual Communications Review, 1961, 9 (3).

Skinner, B.F. Science of learning and the art ofteaching. Harvard Educational Review, 1954,

128, 86-97.

Skinner, B.F. Teaching machines. Science, 1958,128, 969-977.

Smith, D.E.P. Speculations: Characteristics ofsuccessful programs and programmers. In E.Galanter (Ed.), Automatic teaching: The stateof the art. New York: Wiley, 1959.

18

Smith, K.U., & Smith, 'IF. Cybernetic principlesof lewd,. and educational design. New York:Holt, Rinehart, and Winston, 1966.

Vverde, H., & Morgan, R. influence on studentc-hievement of redundancy in self-instructionalmaterials. AMRL-TR-68-75, Wright-PattersonAFB, Oldo: Aeromedical Research Laboratory,1968.

Vernon, M.D. Perception and under tanding ofinstructional television programs. BritishJournal of Psychology, 1953, 44, 116-126.

19

11

APPENDIX I. SCRIPT OF THE AUDIO-V1SUAL MODULE PROGRAMMEDTO TEACH THE RUDIMENTS OF THE DIGESTIVI-L SYSTEM

The slides that you are about to see, and the recording hat you are now listening to, will cover thedigestive system. Chapter 7 in your programmed anatonomy cad physiology text also presents ads system.Let us examine, for a short while, the essentials of this system without the aid of your text.

Slide 1 This slide gives you a clear look at all of the organs arid glands that make up th iigestivesystem. You will notice that all structures have been numbered but not in any ordei. There areseveral structures that are not a part of the digestive system, but their relationslw, io adssystem must and will be explained. Starting with the left portion of the siiae s lookcarefully at the shape and location of each structure and name it.

First we have the starting point of this digestive E;ysteru, number 2 Of the mouth . In xt mouthor oral cavity, we find the teeth and the tongue.

Number 3 points to a lid-like structure, not a pakt of this systen that we call the ei,--igjoitis.Spelled EPIGLOTTIS. The epglottis forms a covering over the windpipt; when food beingswallowed.

Number 6 is the windpipe that we just mentioned. Meoical name is the trachea. :1;pelledTRACHEA. Number 7 points to the liver and notice if you wili, the size of the liver, muchlarger I'm sure than most people realize.

Number 11 points to a small organ just under the liver. Its name is the gallbladder. SpelledGALLBLADDER.

Number 12 points to the small intestines.

Number 13 to the appendix. Spelled APPENDIX. It projects inferiorly from the large intestine,near where the lage and small intestines are joined.

Number 14 is the rectum. Spelled UCTUM. The openings of the rectum and the very end ofthis system are called *fie anus.

Moving now to the right s'de of our slide we see number I which points to the three glands thatwe collectively call the salivary glands. Spelled SALIVARY.

Number 5 points out the foodpipe or esophagus. Spelled ESOPHAGUS.

Number 8 is the stomach_

Number 9 the gland located behind the stomach - the pancreas. Spelled PANCREAS.

Number 10 points out the very first loop of the small intestine. It is .zalled the duodenum.Spelled DUODENUM, also pronounced Duochenum.

Number 15 labels the large intestines.

N3W, as I call out the nunTher, I want you to respond with the correct medical name. Ready?

Ail right.

2

Cotrect the mouth is the beginnin of the Digestive System, and 's here in the oral cavitythai we have 2 othtz organs of digestion the teeth and the tongue.

Correct - the salivary glands.

1

4

- the back of the throat is the pharynx.

13

5

That is correct the esophagus or foodpipe are one in the same.

8

, the stomach.

1 2

Yes, you are n It's the small intestine.

10

The word is pronounced either duodenum or duochenum.

1 5

Right, the large intestine.

1 3

The appendix is correct.

14

Correct, the rectum is th last portion of the large intestine.

7

Tha 's correct, the liver.

1 1

gallbladder lies under the liver.

9

Very good, the answer is the pancreas.

The overall function of tlus digestive system, as I'm sure you realize, deals with food, andinvolves the ingestion and digestion, absorption and elimination of food.

Slide 2 M you can see by this slide, =le main organs of the digestive system form a tube. This tube,that starts with the mouth and ends with the anus, is called the alimentary tract or alimentarycanal. Spelled ALIMENTARY. Looking very closely at this slide - let me name the main organsof the alimentary canal in their correct order:

First, there's the mouth, then the pharynx (they are not shown on this slide), next comes theesophagus, the stomach and then the intestines, both small and large.

Slide 3 Let's review now, in general detail, these main organs of digestion and discuss their individu0functions. The mouth is the beginning or proximal end of this system and tube. Here, in theoral cavity, food enters the alimentary canal under voluntary control.

Slide 4 After the mouth comes the throat or pharynx. It's here that voluntary control of food is lostand involuntary reflex action occurs by way of peristalsis. Spelled PERISLALSIS. Peristalsis isthe involuntary rhythmical muscular movement that propels food through the alimentary canal.

The pharyrot is a passageway for foods between mouth and esophagus. The esophagus orfoodpipe is the next organ in line, and is a passageway for foods between pharynx and stomach.It lies behind or postedor to the trachea.

Slide 5 The stomach is an internal organ and you may roc& from your muscular systern, that smoothmuscle in flat layers or sheets is found in internal organs. This slide is a good picture of justthat.

S ide 6 Tins slide gives you some idea of the shape and internal structure of the stomach with theesophagus opening into the upper portion and the duodenum coming off of the latent-inferiorpart. Here, food is .put through a churning action and partial digestion occurs with theproduction of gastric juice. Here's a bit of nice-to-know information. Drugs and Oehohol arereadily absorbed in the lining of the will '1.

Slide 7 The intestines, both small and large, form the last part of the alimentary canal. In this slide wesee most of the small intestines but part of the large is visable also. The first intestines that weencounter after the stomach are the small intestines. Most digested food absorption takes placehere.

Slide 8 The very first portion of the small intestine is called the duodenum. This slide shows just theduodenal loop.

Slide 9 Here we see the duodenum in relationship with other stmctures in that area. This loop is veryimportant because many digestive juices enter the alimentary tract at this point, digestive juicessuch as pancreatic and bile.

Slide 10 Here in this slide is pictured the large intestliie, including the last sev n or eight inches, calledthe rectum It's in the large intestine that moq water absorption takes place, along withelimination of body water. Also in this slide, the appendix is visible, located near the junctionof the small and large intestine. It has no known function.

Tilat completes our coverage of the main organs of digesfion and before we turn our attentionto the accessory organs of digestion, there are several important points that must made.

Slide 11 First of all, there are two types of digestion, mechanical and chemical. Mechanical digestioncovers all the physical changes in food, and the movement of foods in the alimentary canal.Chemical digestion is concerned with all the chemical changes that occur to foods in the canal.

Slide 12 The first three (carbohydrates, proteins, fats ) listed here must be changed chemically before thebody can make use of them The last three vitamins, minerals, and water) do not have to bechemically changed.

Slide 13 Here we make a statement that we hope will simpFfy this system a little more, so that you willgain a quicker understanding. The main point is that digestive juices must be secreted if achemical change is to take place. In the digestive juices we find certain substances call enzymes.Spelled ENZYMES. Enzymes must be present for chemical action if change is to occur.

Slide 14 This definition of the word metabolism is not difficult to understand. The body must use orutilize foods to remain healthy and alive. This utilization of food for heat, energy, growth andrepair .3 called metabolism.

Slide 15 Carbohydrates and fats are both needed by the body, primarily to supply heat and energy.

Slide 16 Proteins are necessary for growth and the repair of body tissue.

Slide 17 Vitamins, minerals, and water are essential for the life processes, such as growth, energyproduction, reproduction, and resistance to disease.

Now with these points fresh in our minds, we can better understand the functions of theaccessary organs of digestion.

Slide 18 The first of the accessary organs happens to be the salivary glands. This slide shows us wherethey are generally located. The salivary glands secret saliva which aids in the digestion ofcarbohydrates. The teeth and tongue both are considered accessary organs and are located herein the oral cavity. The function of the teeth in the oral cavity. The function of the teeth isprimarily the chewing of foods. The tongue aids the swallowing of foods.

Slide 19 Gastric or stomach juice, secreted by the stomach, is concerned with digestion of proteins.

Slide 20 The liver, as pictured here, covers a good part of the abdorrdnal area. It is the largest gland inthe body. Digested foods, as they are taken into the blood, are carried by the blood directly tothe liver.

Slide 21 The liver has many, many jobs to perform but its prime function is manufacturing and secretinga substance called bile. Bile is necessary for the "breaking-up" of fats, and comts in contactwith food in the duodenum.

Slide 22 Here we see the relationships of the liver with the duodenum, and most importantly the storageshed for bile, the gallbladder. Bile is made and secreted by the liver but stored by thegallbladder.

Slide 23 This slide shows thc last accessary organ that we will discuss, the pancreas. The pancreas secretsa pancreatic digestive juice which aids in the digestion of starches and comple:os the digestionof fats. Remember bile breaks up fat but complete digestion is left up to the pancreatic juice.Proteins are partially digested by this pancreatic juice.

Slide 24 This slide shows the location of the pancreas, which is behind the stomach and its relationshipwith other structures in that area.

The accessory organs of digcs-tion are 1 sted as the teeth, tongue , salivary glands, liver,gallbladder and pancreas.

Slide 25 Now in review, follow along with me as I again name the structures of the digestive system andexplain their functions.

Number 2: mouth, oral cavity, teeth and tongue

Number 1: salivary ginds

Number 4: pharynx

Number 5: esophagus

Number 8: stomach

Number 12: small intestine

Number 10: duodenum

Number 15: large intestine

Number 14: rectum, anus

This completes our discussion of the digestive system.

16

APPENDIX IL PRETEST

Fifty percent of the test covered the first six chapters of the programmed text (The Organization ofthe Human Body, The Skeletal System, The Muscular System, The Nervous System, The CirculatorySystem, and The Respiratory System ), and 50 percent covered Chapter Seven (The Digestive System

1. knother name for bone growth is the The fluid portion of blood is calledprocess of a. corpuscles.a. bone development. b. plasma.b. ossification. c. lymph.

d.marrow production.calcium composition.

d. hemolys n.

2. Arterioles and venules are connected bya. veins.b. vesicles.c. ureters.d. capifiaries.

Deep sleep is a result of completedominance.

a. parasymp atheticb. CNSc. ANSd. sympathetic

The function of the nervous system is tocontrol thea. flow of information in our brains.b. movements of smooth muscle.c. activities of our body.d. prevention of serious injury or dunage

to the body.

5. The three main parts of the skeletal systemarea. muscles, ligaments, and bones.b. bones, joints, and ligaments.c. joints, bones, and cartilage.d. bones, cartilage, and muscles.

The eyeblink and the hiceouofa. reflexes.b. stimuli.c. contraction.d. nervousness.

_ are examples

7. A function of the skeletal system that isprovided by bone marrow isa. holding two bones together.b. support of the body.c. movement of muscles.d. production of blood cells. 24

Which of the following is not a function ofthe skeletal system?a. blood cell productionb. protection of internal organsC. support of the bodyd. supplying body cells with 02

10. When a neural impulse travels from oneneuron to another, this event is called aa. synthesis.b. synapse.c. syndyne.d. synopsis.

11. The walls of various intern0 organs containlayers of muscle.a. smoothb.C.

d.

longshortfree

12. The two main units of the CNS area. receptors and axons.b. nerves and muscles.c. efferents and dividers.d. spinal cord and brain.

he

Nutrients pass from the blood vessels tobody cells througha. tympanic antrums.U. capillary walls.c. metabolic action.d. aortic venae.

14. A group of tissues united or arrangedperform a specific function is called a(n)a. cell.b. organ.c. bone.d. system.

15_ What controls the direeion of bloodwithin the heart?a. aortab. valvesC. ventriclesd. atria

ow 23. The nervous system becomes aware of whatis happening inside and outside the body byway ofa. sensitive axons.b. sensory neurons.c. sensational interstices.d. sensarnatic impulses.

16. The way a cell is organized permits certainmaterials to enter and leave throughin the membrane.a. breaksb. windowsC. entrancesd. pores

17. Th.e muscl . controlling lung action is calledthea. iliacus.b. trapezius.c. diaphragjn.d. supinator.

Inhaled air passes from the nose or mouthinto thea. soma.b. pharynx.c. esophagus.d. trachea.

19. Which blood vessels carry blood away fromthe heart?a. veLns and arteries.b. veins and venules.c. arteries and arterioles.d. ventricles and veins.

The sensitive end of a sensory neuion iscalled a(n)a. receiver.b. autonomer.c. developer.d. receptor.

21. Any change in the environment detected bya receptor is called a(n)a.b.c.d.

stimulus.alveolus.stereobus.simulance.

22. The heart is composed of what type otissue?a. cardiacb. osseousc. cartilaginousd. ventricular

18

24. The smallest organized unit of the nervoussystem is thea.b.c.d,

acton.axon.neuron.neurose.

25. The ANS serves to control most of theactivity of the body.

responsiveb. generativec. unlearnedd. motor

26. The pharynx isdigestive system?a. lateralb. proximalc. extensived. distal

near wha point of the

27. Three substances which undergo chemicaldigestion area. fats, proteins and minerals.b. proteins, vitamins and mimrals.c. vitamins, carbohydtates and proteins.d. carbohydrates, proteins and fats.

28. Which of the following is not a part of thetube called the alimentary canal?a. mouthb.C.

d.

larynxpharynxstomach

29. The trachea isesophagus?a. anteriorb. inferiorc. posteriord. superior

to the

30. The esophagus is a food passageway betweenthe and _

a. throat and pharynxesophagus and gutsstomach arid oral cavitypharynx and stomach

The liver secretes an emulsbreaking action on?a. proteinsb. fatsc. carbohydratesd. minerals

that sta

At what point does bile and pancreatic juicefirst enter the alimentary canal?a. duodenumb. stomachc. esophagusd. colon

33. The two types of digestion are: mechanicaland gastrica. trueb. false

34. The teeth tongue and salivary gl2nds arefound in the cava. duodenum

digestiveabdominaloral

C.

35. Physical movement of foods is part ofa. mechanical digestionb physical digestionc. accessory digestiond. chemical digestion

The rectum is near the end ofits respective system.a. medialb. proximalc. distald. progressive

37. The large intestines are concerned with theabsorption Of?

alcoholwaterdrugsfood

a.b.C.

d.

Foods pass g distal to the pharynx a eunder what kind of control?a. voluntaryb. entensionc. involuntaryd. non-voluntary

19

39. Pro eins aid in tissue repaira. trueb. false

40. Metabolism is concerned with?a. body's ability to utilize foodsb. tissue productionc. energy distributiond. function operation

41. The pancreas is located p s erior to the?a. kidneysb. esophagusc. stomachd. large intesiines

The gallbladder storesa. insulinb. bilec. pancreatic juiced. fats

43. Pancreatic digestive juice completes thedigestion ofa. carbohydratesb. proteinsc. fatsd. bile

44. The main organs of digestion are?a. mouth, pharynx, esophagus, stomach,

intestinesb. throat, foodpipe, stomach, intestinesc. mouth, throat, stomach, small

intestinesd. oral cavity, abdo inal canal, anal

canal

45. The first 10 inches of the small iritestines isthe?a. duodenumb. trachea loopc. pancreas canald. bile duct

46. Food is moved through the esophagus,stomach and intestines bya. alistalsisb. peristalsisc. motostalsisd. musculostalsis

47. Carbohydrates are used by the body toa. build new tissuesb. build new chemical substancesc, provide heat and enerud. repair new tissues

48. The alimentary canal is part of thea. circulatory systemb. respiratory systemc. nervotis systemd. digestive system

20

49. Bile is produced and secreted by the liver.a. trueb. false

50. What is the largest gland in the body?a. pancreasb. gonadsc. liverd. salivary

APPENDIX III POSTTEST

All of the test covered the Digestive System.

1. What structure identifies the most proximalpoint of the digestive system?a. mouthb. phaiynxc. nas; passaged. esophagus

2. The food passageway between the phaand stomach is thea. throatb. esophagusc. duodenumd. bile duct

Name the two types of digestiona. physical and mechanicalb, traumatic and physicalc. chemical and movementd, mechanical and chemical

nx

Carbohydrates and fats are needed by thebody for what reason?a. heat and energyb. muscle repairc. enduranced. metabolism

5. Pancreatic juice first enters which part of thealimentary canal?

8. The largest gland in the body is thea. spleenb. liver

pancreaspharynx

9. The movement of food alo g the alimentarycanal is part ofa. physical digestionb. chemical digestionc. mechanical digestiond. both b & c arc correct

10. Food passing through the alimentary canaldistal to the pharynx is under

controla. voluntaryb, involuntaryc. both a & bd. neither a or b

11. The anus is at therespective systema. distalb. medialc. proximalC. digestive

end o_ its

12. Most water absorption occu s in thea. stomach a. stomachb. duodenum b. duodenumC. bile duct c. large intestined. colon d. small intestine

6. Which of the follov.ing secretes an e ulsifierof fats?a. liverb. stomachc. pancreasd. salivary glands

There are three accessory organs found inthe oral cavity. Name them.a. gastric, tongue, glandsb. teeth, pharynx, nasalc. tongue, food passageway, teethd. teeth, tongue, salivary glands

21

Tissue repair in the body is accomplished bya. minerals and waterb. proteinsc. carbohydrates and fatsd. vitamins

14. The body's ability to utilize foods is calleda. peristalsisb. digestionalismc. metabolismd. utilization

15. The gland located behind the stomach is the 21. The organ that stores bile is thea. duodenum a. gallbladderb. gallbladder b. duodenumc. salivary c. bile ductd. pancreas d. liver

16. Vitamins, minerals and water are necessaryfora. life processesb. movement of foodsc. chemical absorptiond. energy production

17. -The pharynx is a passageway between themouth and thea. esophagusb. windpipee. trachead. duodenum

What organ has the specific functionproducing bile?a. pancreasb. glbladderc. trachead. liver

What substance completes the digestion o_fats?a. liverb. bilec. gallbladderd. pancreatic digestive juice

22. The accessory digestive organs area. teeth, tongue, salivary glands,

pancreas, liver, gallbladderb. teeth, tongue, salivary glands, spleen,

liver, gallbladderc. teeth, salivary glands, spleen, pancreas,

gallbladder, liverd. tongue, spleen, pancreas, gallbladder

23. Bile is secreted by thea. duodenumb. pancreasc. gallbladderd. liver

24. The alimentary canal is rara. circulatory systemb. respiratory systemc. digestive systemd. nervous system

the

20. Gastric juice is secreted by the 25. Duodenum is the name given to a part oa. live r a. large intestinesb. mouth b. pancreasc. tongue c. stomachd. stomach d. small intestines

ATPENDIX IV. SUPPLEMENTARY STATISTICAL TABLES

Table 8. Means and Standard Deviations of TestScores Available for Trainees

(N 112)

Test Mean SD

Posttest 19.5804 33521AFQT 62.7053 14.4131AQE Gen 74.7321 10.5659AQE Admin 70.9911 14.1868AQE Mech 583232 23.2251AQE Elec 66.9018 17.4122Wk-1 Anat&Phys 46.4553 9.1039Quickword 68.9375 14.0579

Note.Pretest statisfics were excluded from thisparticular table since not all subjects were given this test;these statistics are _esented later in the report. TheAFQT and the four AQE scores were available in per-centiles only; consequently, the Means and standarddeviations reported for these tests are percentile statistics.

Table 9. Correlation Matrix of Test Scores

Post-Test test AFQT AQE Gen AQE Admin AQE Mech AQE Elec

Wk.1Anat&Phys

Quick.word

PosttestAFQTAQE GenAQE AdminAQE MechAQE ElecWk-1 Anat&PhysQuickword

.255 .401.401

.246

.223

.500

.285

.455

.668

.195

.315

.472

.699

.431

.727

.516.306.471.274.376.342

.242

.113

.216

.234

.093

.287

.111

Note.r .260 is significant at the .01 level, df = 110. For computing this correlation matrix and subsequent multiplecorrelation and analysts of covniance, it was postulated that the transformation from test raw scores to percentile scoreswas 1inea2. At worst, reported correlations were underestimated.

23

Table 10. Summary of the Wheny-Doobttle Methodfor Computing Multiple Correlation,

Criterion Variable: Postte3t

ittemuke F ValuvStep Predictor to

Number Entered R R2 R4 Remove

1 Wk-1Anat&Phys .5158 .2661 .2661 39.8838Quickword .5483 .3007 .0346 5.3865AQE Gen .5678 .3224 .0218 3.4693

4 AFQT .5696 .3245 .0020 .32315 AQE Mech .5698 .3246 .0002 .0262

Note.-For R .5698; SE of EST 28.1900; MSRegression 8093.074; F(5,106) 10.190; p < .301. Apredictor variable was added or removed from theregression equation according to the following three rules:(1) if there were one or more predictors in the regressionequation whose F value was less tban .005, the one withthe singles,: F value was removed; (2) if no predictor isiemoved by (1) and there were one or more predictorsnot in thc regession equation which had tolerance valuesgreater than or equal to .001, the one with highest F valueamong all predictors was added; and (3) if no predictorwas removed by (1) or added by (2) and there were oneor more predictors not in the regession equation whichpassed the tolerance test, the one with highest F valuegreater than F to enter,01, was added.

Table 11. Regression Coefficients and Their Respective t Values for Test Concomitantsto Posttest Performance, Factors: Pretest and Programmed Medium

Test FQTAQEGen

AQEMed,

Wk-1Anat&Phys

Quick-word

RegressionCoefficient .0203 .0461 -.0111 .1147 .0611

Computedt Values .8941 1.1493 -.6341 3.0755* 2.6352*

Note.-MS Regression = 6.6882;T(5, 75) = 7.5357; p .001.*p < .01; df = 75.

24

Table 12. Regression Coefficients, Standard Errand t Values for the Multiple Concomitant

Variables Used in the One-wayAnalysis of Of'variance, Reported

for Total Source of Variation

Table 13. Regression Coefficients and TheirRespective t Values for Tests Concomitant

to Posttest Performance, Factors:AFQT and Programmed Medium

Wk-1Test AQE Gen Anat&Phys Quickword

CovariateRegressionCoefficient SE t Value

RegressionCoefficient .0506 .1113

Compu tedt Value 1.2221 2.8616*

.0649

1.9527

AFQTAQE GenAQE AdminPretestWk-1 Anat&Phys

.0512

.0320.0445.1280.0987

.0335

.0459J0292.0832.0513

1.5273-.69711.52721.53841.9221 ote. MS Regression = 7.6670; F(3,

p < .001.7 = 9.3975;

Note.-None of these t values are significant at the .01level, df = 43. This analysis was computed using testscores obtained from subjects in Classes 1 (n = 25) and 2(n = 20) only. One subject's set of scores had been care-lessly omitted from this analysis, hence the discrepancy inthe N reported for Class 2 here and in Table 1.

*p < .01; df = 73.

Table 14. Regession Coefficients and TheirRespective t Values for Tests Concomitant

to Posttest Performance, Factors:Week-One Anatomy and Physiology Test

and Progrunmed Medium

Te AFQT AQE Gen Quickword

RegressionCoefficient .0181 .0606 .0720

Computedt Value .8473 1.7036 2.1873*

Note. - MS Regression = 7.9293, Fp <.01.

*p 01; df - 85.

25

85 ) = 4.6314;

UnclassifiedSecurity Class icati ........

DOCUMENT CONTROL DATA - R&D(Security classification of title, body of nbstroct and indexing annotetion must be entered when the overall report is classified)

I. ORIGINATING ACTIVITy (Corporate au hal. )

Technical Training DivisionLo. -3/ Air Force Base, Colorado 80230

za. REPORT SECURITY CLAssiFICATION

2b. GRouP

3. REPORT TITLEEVALUATING AN EXPEMMENTAL AUDIO-VISUAL MODULE PROGRAMMED TO TEACH A BASIC

ANATOMICAL AND PHYSIOLOGICAL SYSTEM

_4. DESCRIP Ti V E NOTES (Type of report end Inclusive &Tues..,

Final Report _ay 1970 to Sept mber 970)5. AU THOR(S) (First na , middle Initial, n )

Pat-Anthony Federico

REPORT DATEJuly 1971

7a. TOTAL NO. OF PAGES

25

7b. No, Or REFS27

_ CONTRACT OR GRANT NO.

b. PROJECT NO. 1121

.. Task No. 112101

d. Work Unit No. 112101002

ga. ORIGIN TOR'S REPORT NU BE )

AR 1L-TR-71-37

eb cs-ri-i ER REPORT NO(S ) Any other numbers that may be assignedthis report)

0 I TRI BD TION STATEMENT

Approved for public release; distribution unlimited.

1 UP .m. E TARY NOTE5 2 SPONSORING MILITARY ACTIVITY

Technical 'Iraining DivisionLowry Air Force Base, Colorado 80230

A BSTR A C T

This study evaluated the learning efficiency and effectiveness of teaching an anatomical and physioloOcal systemto Air Force enlisted trainees utilizing an experimental audio-visual programmed module and a commercial linearprogrammed text. It was demonstrated that the audio-visual programmed approach to training was more efficient thanand equally as effective as the programmed text approach to training. It was determined that trainees of differentlearning abilities acquired as much knowledge about the digestive system from viewing the 20-minute audio-visualmodule as from interacting for 80 to 120 minutes with the programmed text. It was establiGhed that students whodiffered in their mastery of the rudiments of anatomy, physiology, and medical terminology performed equally wellafter audioNisual instruction or after written progrunmed instruction. It was found that trainees reported more positivereactions to the audio-visual program than to the written progrm. It was recommended that within the Medical ServiceFundamentals Course audio-visual programmed instruction be emphasized and written linear programmed instnictionbe de-emphasized.

DD FORM 473, NOV 651 UnclassifiedSecurity Classifica on

UnclassifiedSeeurt y Cla cat

technical trainingmedical service trainingteaching anatomy and physiology2ducational mediaevaluating mediaaudio-visual instruc donprogrammed instructionhuman learning

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