SENIOR MEDICAL STUDENTS KNOWLEDGE AND ATTITUDES TOWARDS BIOSTATISTICS Faculdade de Medicina da Universidade do Porto Introdução à Medicina – 2007/2008 Class 8

 Introduction  Aims  Methods  Study Participants  Data Collection Methods  Survey Description  Variables Description  Stastical Analysis  Results  Discussion  Acknowledgments  Authors

For this, we used an adapted survey used on an American study - «Medicine Residents’ Understanding of the Biostatistics and Results in the Medical Literature» JAMA, which had the same goals as our study. Biostatistics is an important and often disregarded aspect of medical education. In this way, we developped a study, enquiring senior medical students attending to our college – Faculdade de Medicina da Universidade do Porto (FMUP) – in order to understand: ► their medical literature reading habits; ► the relevance they give to biostatistics; ► their capacity to analyse and interpretate biostatistic data.

Main aims:  To understand students attitudes towards biostatistics, namely their medical literature reading habits;  To evaluate senior medical students on their knowledge on analysing biostatistics data;  To identify which factors have influence on their knowledge on biostatistics and on their medical journals reading habits. Secondary aims:  Compare our results with the results obtained in the study we based on. (“Medicine Residents' Understanding of the Biostatistics and Results in the Medical Literature”; JAMA; 2007).

Study participants were selected among the 5 th year medical students of Faculdade de Medicina da Universidade do Porto. 7 classes (194 students) 4 classes selected (class 2, 3, 5 e 6) Potential sample: 87 students As we had a small response rate in our last presentation, we decided to enlarge our sample to all the medical students attending to the 5 th year Potential sample: 194 students

After the changes we made to the sample and with a response rate of 41%, our analysed sample is composed by 80 medical students attending to 5 th year of Faculdade de Medicina da Universidade do Porto, in which:  35 (43,8%) are men;  45 (56,3%) are women. From the 194 students on the 5 th year, 120 (62%) are women and 74 (38%) are men. So, even though the fact our population have more women than men, men’s response rate (47,3%) is higher than women’s response rate (37,5%).

We delivered the paper based questionnaire through the cooperation of some 5 th year students - group I, and also through AEFMUP (Associação de Estudantes da Faculdade de Medicina da Universidade do Porto) - group II. «Medicine Residents’ Understanding of the Biostatistics and Results in the Medical Literature» (JAMA, 2007) During the background research we found in the article «Medicine Residents’ Understanding of the Biostatistics and Results in the Medical Literature» (JAMA, 2007) a survey which focused the same aspects that based our project. We analysed, translated and adapted this questionnaire and used it as our data collection instrument.

Group IGroup II Total n (%) Number of surveys recieved 30 (37,5%)50 (62,5%)80 (100%) Gender Males12 (27,9%)31 (72,1%)43 Female18 (46,6%)19 (53,4%)37 Medical Literature Reading Habits I do not read.23 (45,1%)28 (54,9%)51 Foreign Journals5 (20%)20 (80%)25 National Journals2 (50%) 4 Knowledge Level [10,14[11 (35,5%)20 (64,5%)31 [14,17]4 (28,6%)10 (71,4%)14 ]17,20]15 (42,9%)20 (57,1%)35 The response rate through 5th year medical students was 38,0% and the response through AEFMUP was 43,5%. AEFMUP was a more efficient method of delivering surveys, and getting a higher percentage of solved surveys.

This survey is divided in two different sections and is composed by eighteen questions: First Section:  Individual Questions: - subjective character; - regarding attitudes. Second Section:  Multiple-choice questions : - objective character; - regarding knowledge.

This survey is divided in two different sections and is composed by eighteen questions: First Section:  Two are related with participants description (gender and final grade of Introdução à Medicina);  Six about attitudes and interest on biostatistics;  Four questions in which participants have to evaluate themselves about their abilities on biostatistics. Second Section:  Six to test their knowledge by analyzing data, graphics and their critical position about methods used in several studies.

 Survey adjusts:  introduction of Q2 (final grade of Introdução à Medicina);  in Q3 (medical literature reading habits), we included the discreteness between national and international journals;  introduction of Q8 (importance given to the teaching of Biostatistics in the medical curriculum);  As the original survey was too long, we shortened it by eliminating questions regarding their knowledge.

Our study variables are based on the questions composing the survey. General Variables :  Gender – Q1 (nominal categorical);  Final grade of the subject Introdução à Medicina – Q2 (ordinal categorical). Then, we divided the subsequent variables in two groups: the ones related to attitudes and others related to knowledge on biostatistics. Attitudes Related Variables :  one nominal (Q3) and five ordinal categorical variables (Q4, Q5, Q6, Q7, Q8) related to the interest on biostatics;  four ordinal categorical variables (Q9, Q10, Q11, Q12) related to students self-evaluation on their abilities on the matter.

Knowledge Related Variables :  six ordinal categorical variables (Q13, Q14, Q15, Q16, Q17, Q18) that arise from the second part of our survey. From all these categorical variables, we created three continuous ones, which are: knowledge test grade (Q13, Q14, Q15, Q16, Q17, Q18); interest grade (Q4, Q5, Q6, Q7, Q8) and self-evaluation grade (Q9, Q10, Q11, Q12). All these variables were rated in a scale of 0 to 20.

 The variable Medical literature reading habits (Q3) is dependent of all other variables with which is related on [TABLE1] of the Results section.  The same is applied to the variable Knowledge (final grade of survey’s second part) on [TABLE2] of the same section.  In the relation between the Interest on Biostatistics (Q4) and the Importance given to this subject (Q8), Q4 is dependent of Q8.

 SPSS 15.0 for Windows ® ― analysis of collected data through the survey;  Tests used in data analisys: ► Mann-Whitney test; ► Chi-square test; ► T-Student test; ► One Way ANOVA.

Significant relations found:  Medical journals reading habits (Q3) and Interest on learning more about biostatistics (Q4) – p=0,003 [TABLE 1];  Importance given to biostatistics in Medicine Curriculum (Q8) and Interest on learning more about biostatistics (Q4) – p=0,001;  Importance given to biostatistics in Medicine Curriculum (Q8) and Knowledge – p=0,028 [TABLE 2];  Interest on learning more about biostatistics (Q4) and Knowledge – p=0,015 [TABLE 2 and GRAPHIC 1].

Characteristic Medical Literature Reading habits ReadDo no read p-value n (%) Q4 a I disagree6 (7.5%)29 (36.3%) 0.03**** Neutron10 (12.5%)14 (17.5%) I agree13 (16.3%)8 (10%) Q5 b I disagree7 (8.8%)19 (23.8%) 0.371**** Neutron16 (20%)20 (25%) I agree6 (7.5%)11 (13.8%) Q6 c I disagree3 (3.8%)1 (1.3%) 0.327**** Neutron5 (6.3%)11 (13.8%) I agree21 (26.3%)39 (48.8%) Q7 d I disagree4 (5%)3 (3.8%) 0.295**** Neutron6 (7.5%)7 (8.8%) I agree19 (23.8%)41 (51.3%) Q8 e I disagree4 (5%)6 (7.5%) 0.779**** Neutron5 (6.3%)12 (15%) I agree20 (25%)33 (41.3%) * T-test ** One way ANOVA *** Mann-Whitney Test **** Chi-Square Test a “If I had a chance, I would live to learn more about biostatistics.” b “I can understand almost all of the statistical terms I encounter in journal articles.” c “I believe that biostatistics is valid scientific methodology.” d “To be an intelligent reader of literatute, it is necessary to know something about biostatistics.”. e “Biostatistics teaching is important on the medical curriculum.”. TABLE 1 - Medical Literature Reading Habits (Q3) related with the remain variables from the survey first section which regards attitudes (Q4-Q8). Those who revealed to be more interest on learning more about biostatistics are the ones who have medical literature reading habits

Characteristic Knowledge Levels n (%)Mean (SD)p-value Gender Male35 (43.8)10.2 (3.3) 0.164* Female45 (56.3)9.3 (3.1) Grade of Introdução a Medicina I did not have this subject1 (1.3) ** [10, 14[11 (13.8)8.0 (2.8) [14, 17]63 (78.8)9.9 (3.3) ]17, 20]5 (6.3)10.0 (3.1) Medical Literature Reading Habits I do not read51 (63.8)9.9 (3.1) 0.131** Foreigner Journals27 (33.8)9.5 (3.4) National Journals2 (2.5)5.6 (1.6) Interest on Biostatistics [4, 12[22 (27.5)8.7 (2.8) 0.076* [12, 20]57 (71.3)10.1 (3.2) * T-test ** One way ANOVA *** Mann-Whitney Test **** Chi-Square Test a “If I had a chance, I would live to learn more about biostatistics.” b “I can understand almost all of the statistical terms I encounter in journal articles.” c “I believe that biostatistics is valid scientific methodology.” d “To be an intelligent reader of literatute, it is necessary to know something about biostatistics.”. e “Biostatistics teaching is important on the medical curriculum.”. TABLE 2- Knowledge level related with all the variables that arisen from the first part of the survey; regarding sample characteristics (Q1, Q2), attitudes (Q3-Q8); and the variables created to measure interest and confidence. These variables do not have a significant relation, which means that knowledge on biostatistics is not influenced by students’ interest on learning more about it.

Characteristic Knowledge Levels n (%)Mean (SD)p-value Q4 a I disagree/Neutron59 (73.8)9.2 (2.9) 0.015* I agree21 (26.3)11.0 (3.4) Q5 b I disagree/Neutron62 (78.0)9.9 (3.1) 0.371* I agree17 (22.0)9.1 (3.3) Q6 c I disagree/Neutron20 (25.0)9.3 (2.3) 0.537* I agree60 (75.0)9.8 (3.3) Q7 d I disagree/Neutron20 (25.0)8.9 (2.6) 0.148* I agree60 (75.0)10.0 (3.2) Q8 e I disagree/Neutron27 (33.8)8.6 (2.4) 0.028* I agree53 (66.3)10.3 (3.3) Self-evaluation [4, 12[46 (57.5)9.8 (3.3) 0.685*** [12, 20]34 (42.5)9.5 (2.9) * T-test ** One way ANOVA *** Mann-Whitney Test **** Chi-Square Test a “If I had a chance, I would live to learn more about biostatistics.” b “I can understand almost all of the statistical terms I encounter in journal articles.” c “I believe that biostatistics is valid scientific methodology.” d “To be an intelligent reader of literatute, it is necessary to know something about biostatistics.”. e “Biostatistics teaching is important on the medical curriculum.”. TABLE 2- Knowledge level related with all the variables that arisen from the first part of the survey; regarding sample characteristics (Q1, Q2), attitudes (Q3-Q8); and the variables created to measure interest and confidence. Knowledge on biostatistics is influenced by the importance given to it.

GRAPHIC1: Relation between knowledge and interest on biostatistics (Q4). Those students who reveal to have higher interest on learning more about biostatistics are the ones who obtained better results on the knowledge test. T-Students Test - p=0,015

We can not make a correct comparison between the studies, but it seems that there is not many differences between American and Portuguese’s medical students knowledge on biostatistics. QuestionsObjective Correct Answers (%) FMUP’s studentsJAMA article Q13-a Identify continuous variables82,543,7 Q13-b Identify continuous variables51,341,5 Q13-c Identify continuous variables73,832,9 Q14 Recognize the purpose of double- blind studies 88,887,4 Q15-a Identify ANOVA46,347,3 Q15-b Identify Chi-Square Test26,325,6 Q15-c Identify T-Student Test46,358,1 Q16 Interpret 95% CI and statistical significance 2,511,9 Q17 Determine which test has more specificity 56,356,7 Q18 Interpret odds ratio in multivariate regression analysis 3537,4 [ TABLE3]: Percentage of correct answers to the common question of our study and the American study «Medicine Residents’ Understanding of Biostatistics and Results in the Medical Literature» (JAMA, 2007).

The main conclusion we take was that it is not the medical literature reading habits, but the interest on learning more about biostatistics that has influence on the level of knowledge. At the same time, medical journals reading habits is related to the students’ interests. So, this allows us to say that students which are more interested are the ones who read more medical journals and the ones who knows more about biostatistics.

 Our study limitations are:  small sample constituted only by medical students from the 5th year and from a single medical school – Faculdade de Medicina da Universidade do Porto;  the possibility that students may have not paid the correct attention while they were answering the survey;

The comparison between our study and the American study published on JAMA – «Medicine Residents’ Understanding of the Biostatistics and Results in the Medical Literature» (2007) – thought the application of statistical tests is impracticable because:  our target population is slightly different from theirs, as we enquired senior medical students, while their target population referred mostly to interns;  their sample was divided in several groups with different characteristics ;  the survey we used was not exactly the same they used, as we find the need to adapt the latter to a Portuguese context.

We would like to thank to all the 5 th year medical students that cooperate with us. Without their help and availability this work wouldn’t be possible. Subject’s Main Professor: Altamiro da Costa Pereira, MD, PhD Adviser: Armando Pinto, PhD

Ana Carolina Araújo Ana Margarida Mesquita Ana Mafalda David Ana Sofia Correia Clara Gomes Joana Silva João Afonso José Pedro Salvador Maria Gabriel Jacob Marta Gomes Nádia Fakir Ricardo Matos Rui Morais Solange Gonçalves Class 8