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Stress levels in Portuguese 1st year medical students
Ana Filipa Marques; Ana Rita Soares; Carlos Filipe Neves; Emanuel Brilhante; Joana Filipa Tavares;
João Pedro Freitas; Mafalda Correia; Mariana Gomes; Pedro Tavares; Vítor Silva.
Prof. Dr. Armando Teixeira-Pinto. Class 21
ABSTRACT
Stress is a problem that affects students, especially medical students who are known for their
stressful life. In the case of first year medical students, levels of stress may be in fact high. This study
may be considered innovative since it pretends to identify general causes of stress and not specific
factors related to school environment or type of learning. Besides that, we consider that focusing on
first year students, we may analyse the stress factors of a special population, in which is present an
important stress factor - the transition to college.
Therefore, this study pretends to assess stress levels among first year medical students and
identify some factors related to those levels.
Accordingly, we have defined the 280 first year medical students of Faculty of Medicine of
Porto University as our sample. To find out the incidence of stress in those medical students, they
were asked to complete a questionnaire – General Health Questionnaire-12 – and some questions
about factors related to stress. Then, the results of this cross-section study were statistically
analyzed, using SPSS program. Therefore, we created a histogram to evaluate if the variable stress
followed a normal distribution. As the results were unclear we proceeded with a Kolmogorov-Smirnov
test, and concluded that the data doesn’t follow a normal distribution. But, since Kolmogorov-Sminorv
test is very sensible we analyzed variables using t-tests. As we didn’t obtain any statistical significant
values, we decided to use non-parametric tests, namely Mann-Whitney U and Kruskal-Wallis. We
also didn’t obtain any results, so in our final analyses we categorized the levels of stress in three
categories (low, medium and high or very high stress). Finally we used frequencies tables as
summary measure and analyzed the results through crosstabs and chi-square tests, considering 0,05
our statistical significance level.
All the chi-square tests showed that there is no significant relation between the variables
(gender, attending for the first time to an undergraduate course, being away from home, living alone,
practicing extracurricular activities, having a boyfriend/girlfriend, being a part-time student, smoking,
hours of study, hours of sleep and zodiac sign) and the levels of stress, since p value is always
higher that 0,05.
In conclusion, the percentage of students with low and medium stress levels is higher than the
percentage of students with high or very high stress levels of stress and all the variables that were
analyzed didn’t show any significant relation with stress levels.
KEY-WORDS: Stress; Medical; Students; University; Porto.
INTRODUCTION
Stress is the body’s specific answer – emotional, physical or cognitive – when it is exposed to
an external stimulus, which requires a greater response than the one it is used to giving.
Nevertheless, stress can be a positive factor and it is always present, although its intensity changes:
it is very low when a person is resting or sleeping and extremely high after a severe accident.
In this manner, society’s concern about stress has been increasing because, nowadays, this
problem affects a very large number of people and is felt earlier in life. Therefore, it is in our best
interest to analyse this subject. In this way, this project will broach one of the most stressful factors in
young people – entering University.
In fact, it is important to study the levels of stress of first year university students because
entering and attending a degree at university implies huge changes concerning responsibility,
working habits as well as transformations in the youngsters’ social life. Considering all this, some
studies(1,2,3,4,5) point out the amount to learn, the time amounts of the course and examinations as
factors that increase stress levels. On the other hand, uncertainty about individual study behaviour,
fear of failure and inadequacy in social activities are considered important psychological factors.
Lastly, inadequate time for relaxation and for practising other activities is also considered by
university students as stressful factors. Considering all this, it is easy to understand the intimate
relation between high stress levels and mental diseases, such as depression(6,7), as well as with
weight changes(8), both loss and gain. Therefore, it is essential to know whether or not there are high
stress levels in first year university students.
On the other hand, we chose to focus only on medical students, since this course is, at first
glance, extremely stressful, because not only does it require many hours of study, but also because
students have to develop interpersonal skills and self-confidence, in order to be “fully”-qualified
doctors in the future.
In this way, there have been made, as we have already mentioned, several studies about this
subject in other countries. Also in Portugal, it has been made a study to evaluate the stress levels in
first year medical students of Faculdade de Medicina da Universidade do Porto(9). So, our work is
innovative not because it measures the stress levels of Portuguese students. It will be innovative in
the type of stress factors that are analysed. In fact, the study previously made measured not only
factors of a more general character, like sleeping hours and the changes associated to the transition
to college, concerning autonomy, demands and responsibility, but it also focused very specific
factors. Examples of these factors are the evaluation system, FMUP's environment and the fact that
the type of education/learning is focused on memorization. This is shown on the graphic below, which
is a synthesis of a graphic of this study.
So, our study is innovative because we analyse only general factors, which allow us to broad
the results to a larger population. This is very important because the study reaches and is interesting
to a large number of people.
Other than that, this study was about students of all years, while our study analyse only first
year students. We believe that focusing our study on this population, we will be able to analyse the
stress factors of a very unique population in which its present a very important stressor factor – the
transition to college.
RESEARCH QUESTIONS AND AIMS
The study that is being developed has two main objectives. The first one is to assess the stress
levels of first year medical students in a Portuguese medical school. The second objective is to
identify some factors that might be related to academic stress, namely: gender, being away from his
normal residency, attending for the first time to an undergraduate course, having extracurricular
activities, having a partner, being a part-time student, amount of study hours, smoking status, living
alone and sleeping hours.
Our study is of great interest because, although it has been made at least one study about
stress levels in Portuguese students, our project has specific characteristics that make it unique and
important to analyse a population that, according to our research, has never been properly studied.
PARTICIPANTS AND METHODS
Study participants
Regarding the participants, the target population is first year medical students. Accordingly, we
have defined the first year medical students of Faculty of Medicine of Porto University as our sample.
In what concerns sampling methods we chose a non-randomized method, specifically
convenience sampling. In our study the inclusion criteria was being a first year medical student. No
exclusion criteria was defined.
Study design
Concerning the study design, our study is a cross-sectional study.
Data collection methods
In order to collect the data, we used the General Health Questionnaire-12 (GHQ-12) (10). This
questionnaire is a resumed version of the General Health Questionnaire-28 and accesses the
general state of the health of an individual, being the majority of the questions about the
psychological state. The English version of this questionnaire was chosen since it is validated and
scored. The translation was made separately by two translators and then the two versions were
confronted with each other. The final translation was also compared with a translation that had
already been made in another study(9). Finally, we added to the questionnaire the general questions
related to the variables in study. Before the application of the questionnaire to the sample, it was
made a pilot-application in a sample of ten individuals that are not part of the sample.
Regarding the score of the questionnaire, the answers of every question are scored from 0 to
3. So, to obtain the level of stress we some them up. Than, the value obtained is put into one of the
three categories defined from the questionnaire: less or equal to 10 means low stress; from 11 to 15
means medium and more than 15 means high or very high stress.
Variables description
In relation to variables, the dependent variable is the stress level. In what concerns the
independent variables, our aim is to find out if they have a significative relation with stress levels.
Therefore, they can be considered either causes or consequences of stress. In fact, these
independent variables are factors as gender, being away from his normal residency, living alone,
being a part-time student, amount of study hours, attending for the first time to an undergraduate
course, smoking status and sleeping hours. Finally, having a partner and extracurricular activities are
factors that give us these two perspectives because, on one hand, they can be causes of stress by
demanding time and dedication and, on the other hand, they can be factors that minimize stress by
being a distraction, allowing the abstraction from questions related to the course. We also added to
the questionnaire a question about the zodiac sign that will work as a control factor.
We chose to apply the questionnaire during the class of Introduction to Medicine. In order to
do this, we asked the collaboration of the professors to deliver the questionnaire in the first three
minutes of the class. This application was made in the first two weeks of March.
Statistical Analysis
The statistical analysis was performed using SPSS for Windows. Descriptive methods were
used to summarize the data. Since all our variables are categorical, we used absolute and relative
frequencies.
Firstly, we wanted to find out if the variable stress could follow a Normal distribution. So, we
built a histogram and the result wasn’t conclusive enough. Thus, we applied to the Kolmogorov-
Smirnov test, which lead us to reject H0 (H0: the variable stress follows a Normal distribution),
because the value of p (significance level) was lesser than 0,05 (p=0,001). But due to the very high
sensibility of the Kolmogorov-Smirnov and the presence of some stress values that had great
deviation to the mean we analysed the stress level as a variable with a normal distribution. This
analysis didn’t show us any significant relation between the stress levels and the variables in study.
We also consider the variable as a categorical one, which was divided into four categories
accordingly to the questionnaire (low stress levels, medium stress levels, high stress values and very
high stress values). This way, we analysed the results through crosstabs and a chi-square. This
analysis showed that there was a significant relation between the stress levels and the variables
“Having a boyfriend/girlfriend” and “Hours of study”. But, due to the low frequencies of students in the
high and in the very high categories we decided to collapse these two categories in one category
(high or very high stress levels) so that the statistical analysis could be more solid and to prevent
statistical errors. Consequently we performed our analysis of the results through crosstabs and chi-
square tests, using only the final three categories.
Besides considering stress as a categorical variable, we decided to analyse it as a continuous
one, using non-parametric tests. Related to the variables gender, attending for the first time to an
undergraduate course, being away from his normal residency, living alone, having extracurricular
activities, having a partner, being a part-time student and smoking status, we used Mann-Whitney U
test to verify if there was any relation between these variables and the stress levels. To verify if there
was any relation between the variables amount of study hours, sleeping hours and zodiac sign and
the stress levels, we used Kruskal-Wallis test.
At the end, we verified that there was no relation in both situations. Thus, we decided to
consider the stress levels a categorical variable, with the high and the very high categories collapsed,
so that we could achieve more consistence in the applied method.
RESULTS, TABLES AND GRAPHICS
After the questionnaire delivery, there
were obtained 236 answered questionnaires,
out of the 280 first year medical students.
As mentioned before, the stress levels
were divided in three categories. The
distribution in these categories(Table 2 and
Graph 2) is: 38,6%(N=91) of the students
have low levels of stress, 37,3%(N=88) have
medium levels and 23,3%(N=55) have high
or very high levels of stress. Besides this
there were two missing values (0,8%).
Table 1 – Frequency of stress categories
GenderStarting by the variable gender, the frequencies table (Table 2) showed that 64.4% of the
students are female (N=152) and that 35.6% are male (N=84).
Frequency Percentage
Valid
values
Male 84 35,6
Female 152 64,4
Total 236 100,0
Frequency Percentage
Valid
values
Low levels of stress 91 38,6
Medium levels of stress 88 37,3
High or very high levels of
stress
55 23,3
Total 234 99,2
Missing 2 0,8
Total 236 100,0
Graphic 1 – Frequency of
stress categories
Table 2
Table 2 – Frequencies table concerning the sex
According to the crosstab (Table 13) we verify that the percentage of male and female per
each stress category is similar. Consistent with, the chi-square test showed that there is no
significative relation between the gender of an individual and the levels of stress, since p>0,05
(p=0,972). Therefore we accept the H0: Levels of stress on male are equal to levels of stress on
female.
Attending for the first time to an undergraduate course
Related to the variable attending for the first time to an undergraduate course, the frequencies
table (Table 3) showed that 86.4% of the students are away from home (N=204) and 13.6% are not
(N=32).
The crosstab (Table 13) allow us to verify that the percentage of students who aren´t for the
first time at an undergraduate course is higher in the low level of stress category. On the other hand,
the percentage of students who are for the first time at an undergraduate course is higher in the
category of medium levels of stress. In the high or very high category we observed that the
percentage of students who are for the first time at an undergraduate course or not is approximately
the same. The chi-square test shows that there aren’t significative differences, since p>0,05
(p=0,565). Therefore, we accept H0: Levels of stress on students that are attending for the first time to
an undergraduate course or not are equal.
Being away from home
Related to the variable being away from home, the frequencies table (Table 4) showed that
51,3% of the students are away from home (N=121) and 48,7% are not (N=115).
Frequency Percentage
Valid
values
Yes 121 51,3
No 115 48,7
Total 236 100,0
Frequency Percentage
Valid
values
Yes 204 86,4
No 32 13,6
Total 236 100,0
Table 4
Table 4 – Frequencies table concerning being
away from home
Table 3 – Frequencies table concerning attending
for the first time to an undergraduate course
The crosstab (Table 13) show us that there is a higher percentage of students who aren’t away
from home in low stress levels, however there is a higher percentage of students who are away from
home with high or very high levels of stress. In the medium category of stress the percentage of
students who are away from home or not is similar. The chi-square test allows us to verify that this
differences aren’t statistically significative, since p>0,05 (p=0,492). Therefore, we accept H0: Levels
of stress on students that are away from home or not are equal.
Living alone
In what concerns to this variable, the frequencies table (Table 5) showed that 10.6% of the
students live alone (N=25), while 89.4% don’t (N=211).
The crosstab (Table 13) allow us to verify that there are some differences between students
who live alone and not. There is a higher percentage of students who don’t live alone in the low level
of stress category. In the high or very high stress category there is a higher percentage of students
who live alone. In the medium stress level category the percentage of students who live alone and
those who don’t are approximately the same. The chi-square test showed us that those differences
are not statistically significant, because p>0.05 (p=0.543). So, we accept H0: the levels of stress on
students who live alone are equal to the levels of those who don’t.
Having an extracurricular activity
Regarding the variable having an extracurricular activity, the frequencies table (Table 6)
showed that 59,3% of the students practice an extracurricular activity(N=140), while 40,7%
don’t (N=96).
Frequency Percentage
Valid
values
Yes 140 59,3
No 96 40,7
Total 236 100,0
Frequency Percentage
Valid
values
Yes 25 10,6
No 211 89,4
Total 236 100,0
Table 5 – Frequencies table concerning
living aloneTable 6
Table 6 – Frequencies table concerning having
an extracurricular activity
Looking at the crosstab (Table 13), we see that the percentage of students who practice an
extracurricular activity and those who don’t per each stress category is similar. Consistent with, the
chi-square test showed that there is no significative relation between this variable and the levels of
stress, since p>0,05 (p=0,994). Therefore we accept the H0: Levels of stress on students who have
an extracurricular activity and on those who don’t are equal.
Girlfriend/Boyfriend
Related with the present variable, the frequencies table (Table 7) showed that 38.6% of the
students have a boyfriend/girlfriend (N=91) and that 61.4% have not (N=145).
Frequency Percentage
Valid
values
Yes 91 38,6
No 145 61,4
Total 236 100,0
The crosstab (Table 13) allow us to verify that there are a higher percentage of students who
have a boyfriend/girlfriend in the medium stress category. In contrast, the percentage of students who
haven’t got a boyfriend/girlfriend in low and in high or very high levels of stress categories is similar.
The chi-square test shows that there is no significative differences, since p>0,05 (p=0,739).
Therefore, we accept H0: Levels of stress on students that have a partner or not are equal.
Part-time studentRelated to the variable being a part-time student, the frequencies table (Table 8) showed that
3,0% of the students are part-time students (N=7) and that 97,0% aren’t (N=229).
The crosstab (Table 13) allow us to verify that the percentage of part-time students that have
low and medium stress levels is lower than the percentage of non part-time students. On the other
hand, the percentage of part-time students in the high or very high levels of stress category is higher.
However, the chi-square test showed that there is no significative relation between being a part-time
Frequency Percentage
Valid
values
Yes 7 3,0
No 229 97,0
Total 236 100,0
Table 7 – Frequencies table concerning
having a girlfriend/boyfriend
Table 8 – Frequencies table concerning being
a part-time student
student and the stress levels, because p>0,05 (p=0,471). But, since 50% of the cells expected count
less than 5, we chose to do an exact test. The result was p=0,543 (p>0,05). Therefore we accept the
H0: Levels of stress on part-time students are equal to levels of stress on non part-time students.
Smoking
Related to the variable being a smoker, the frequencies table (Table 9) showed that 8,1%
of the students are smokers (N=19) and that 91,9% aren’t (N=217).
Frequency Percentage
Valid
values
Yes 19 8,1
No 217 91,9
Total 236 100,0
The crosstab (Table 13) allow us to verify that there are some differences between students
who smoke and not. There is a higher percentage of students who don’t smoke with low stress levels.
On the other hand, in the high or very high stress category there is a higher percentage of students
who smoke. In the medium stress category the percentage of students who smoke or not is similar
However, the chi-square test showed us that those differences are not statistically significant,
because p>0.05 (p=0.650). So, we accept H0: the levels of stress on students who smoke are equal
to the levels of those who don’t.
Hours of study
Related to the variable hours of study, the crosstab (Table 10) showed that 50% of the students
study less than 2 hours (N=118), 47,9% between 2 and 5 hours(N=113), 2,1% between 5 and 8 hours(N=5).
Frequency Percentage
Valid
values
Less than 2 118 50,0
Between 2 and 5 113 47,9
Between 5 and 8 5 2,1
Total 236 100,0
The crosstab (Table 13) allow us to verify that there are some differences in the levels of
stress between the different groups. We noticed that in the low and medium stress categories there is
a higher percentage of students who study between 2 and 5 hours a day. On the other hand, in the
category of high or very high levels of stress, there is a higher percentage of students who study
Table 9 – Frequencies table concerning
being a smoker
Table 10 – Frequencies table concerning the
hours of study
between 5 and 8 hours a day. However the chi-square test told us that there are no statistically
significant differences, because p>0.05(p=0.407).
But, since 33,3% of the cells expected count less than 5, we did an exact test. The result was
p=0,513 (p>0,05). Therefore we accept the H0: levels of stress of the students who study less than 2
hours are equal to those of the students who study between 2 and 5 and equal to the levels of the
students who study between 5 and 8 hours.
Hours of sleep
Related to this variable, the frequencies table (Table 11) showed us that 3% of students sleep less
than four hours (N=7), 55,8% sleep between four and six (N=130), 30% sleep between six and eight (N=70)
and 11,2% sleep more than eight hours (N=26).
Frequency Percentage
Valid
values
Less than 4 7 3,0
Between 4 and 6 132 55,9
Between 6 and 8 70 29,7
More than 8 26 11,0
Total 235 99,6
Missing 1 0,4
Total 236 100,0
The crosstab (Table 13) allow us to verify that the percentage of students who sleep less than
four hours a day is higher in the low and high or very high levels of stress categories. However, the
percentage of students who sleep between six and eight hours a day is higher in the medium stress
level category. The chi-square test showed us that p=0,385 so, p>0,05. But, since 25,0% of the cells
expected count less than 5, we did an exact test. According to this test, p=0,379. Therefore, we
accept H0: Levels of stress on students that sleep less than 4 hours, sleep between 4 and 6 hours,
sleep between 6 and 8 hours and sleep more than 8 hours are equal.
Zodiac Sign
Analyzing the factor Zodiac signs, the frequencies table (Table 12) showed that 6,8% of the
students are Aries (N=16); 9,4% are Cancer (N=22); 7,7% are Libra (N=18); 10,3% are Capricorn
(N=24); 12,0% are Taurus (N=28); 15,8% are Leo (N=37); 3,0% are Scorpio (N=7); 3,8% are
Aquarius (N=9); 8,1% are Gemini (N=19); 7,7 are Virgo (N=18); 6,8% are Sagittarius (N=16) and
8,5% are Pisces (N=20).
Table 11 – Frequencies table concerning the hours of study
Frequency Percentage
Valid
values
Aries 17 7,2
Cancer 22 9,3
Libra 18 7,6
Capricorn 24 10,2
Taurus 28 11,9
Leo 37 15,7
Scorpio 7 3,0
Aquarius 9 3,8
Gemini 19 8,1
Virgo 18 7,6
Sagittarius 17 7,2
Pisces 20 8,5
Total 236 100,0
According to the crosstab (Table 13) of the variable Zodiac Signs, we verify that in the low
stress level category there is a higher percentage of students whose zodiac sign is Aries. We also
observed that in the medium stress level category there is a higher percentage of students whose
zodiac signs Libra. In the high and very high category we find a higher prevalence of students whose
zodiac sign is Scorpio.
Although the results observed in the crosstab, the chi-square (Table 35) showed that that is no
significative relation between the zodiac signs and the stress levels, since p>0,05 (p=0,376). Since
33,3% of the cells expected count less than 5, we did an exact test. However, the program was
enable to realize it, so we couldn’t obtain the p value. Therefore we used the result of the chi-square
test and accepted H0 (H0: the levels of stress of the students are equal in all signs).
Variable analysis
Stress Categoriesp value (chi-
square)P value (exact
test)
Low levels(%)
Medium levels(%)
High or very high levels (%)
Gender Male Female
39,338,7
38,137,3
22,624,0
0,972
Table 12 - Frequencies table concerning the
zodiac sign
First time on an undergraduate course Yes No
37,945,2
38,929,0
23,225,8
0,565
Being away from home Yes No
36,741,2
36,738,6
26,720,2
0,492
Living alone Yes No
32,039,7
36,037,8
32,022,5
0,543
Extracurricular activities Yes No
38,838,9
37,437,9
23,723,2
0,994
Boyfriend/girlfriend Yes No
37,439,9
40,735,7
22,024,5
0,739
Part-time student Yes No
28,639,2
28,637,9
42,922,9
0,471 0,543
Smoking Yes No
31,639,5
36,837,7
31,622,8
0,650
Hours of study <2h 2h-5h 5h-8h
38,540,220,0
37,638,420,0
23,921,460,0
0,407 0,513
Hours of sleep <4h 4h-6h 6h-8h >8h
57,140,032,942,3
14,333,848,634,6
28,626,218,623,1
0,385 0,379
Zodiac sign Aries Cancer Libra Capricorn Taurus Leo Scorpio Aquarius Gemini Virgo Sagittarius Pisces
68,850,022,229,228,637,814,333,347,438,937,550,0
12,531,855,645,850,040,528,633,342,133,337,520,0
18,818,222,225,021,421,657,133,310,527,825,030,0
0,376
DISCUSSION
During this study, we pretend to access stress levels of first year medical students (we defined
students of Faculty of Medicine of Porto University as the sample) and to identify some factors that
might be related to those levels. In spite of what was expected, we verified that the percentage of
students with low and medium stress levels (38,6% and 37,3%) is higher than the percentage of
students with high or very high stress levels (23,3%). Moreover, all the variables analyzed didn’t
show any significant relation with stress levels. Our results may be explained by some factors such
as, bad quality/wrong interpretation of the questionnaire, lack of encouragement to fill honestly the
questionnaire, incorrect choose of the variables or sample and difficulties to quantify stress.
Tabela 13 – Sum up table of the crosstabs, chi-square and exact tests, resulting from the variable analysis
In order to compare our results with previous studies, we decided to focus on “Estudo da
relação entre o stress e os estilos de vida nos estudantes de Medicina” (9) due to its similarity with our
study. Although this study involved students from every academic year and our study only focused on
first year medical students, both of them meant to measure stress levels in FMUP.
In opposition to that study, which found that 58,2% of medical population had high stress
levels, our results showed that just 23,3% of first year medical students have equivalent levels.
However, we were not able to compare the results between both studies, as the variables in study
were completely different.
Although we didn’t find any significant statistical results, this study can be an important tool in
the study of stress, since it shows the need to invest in the search of new variables that may explain
the stress levels among medical students.
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