Introduction to Medicine I Class 6 Regent Teacher: Altamiro Costa Pereira Supervisor Teachers: Cristina da Costa Santos Gustavo Bacelar

 Title  Keywords  Introduction  Aim  References Different Scales: Different Answers? 2

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 Visual Analogue Scales  Numeric Rating Scales  Questionnarie  Bias  Questionnaire design Different Scales: Different Answers? 4

5 Questionnaire Main tool for collecting data in surveys [1] Research instrument consisting of a series of questions for the purpose of gathering information from respondents about a certain subject In Medicine, questionnaires are developed to measure patient’s opinion Hartman, J.M.(2002); Hogikyan (2002); Pesudovs, K. (2007)

 Investigators have found it difficult to decide … ◦ Is the instrument of measurement appropriate ? ◦ Does questionnaire need to be specially developed for their study? Different Scales: Different Answers? 6 Pesudovs, K. (2007)

Different Scales: Different Answers? 7 Quality of questionnaire results Questionnaire design Questionnaire measurement the choice of scale Choi (2005)

 Distortions of truth, intentional or non-intentional, that change the outcome of the study Different Scales: Different Answers? 8 BIAS Choi (2005); Hartman (2002)

Different Scales: Different Answers? 9 VALIDITY starts when the author antecipates specific biases that might influence the results and he tries to control these biases in the design, conduct and analysis of their work. [1]1 Hartman (2002)

 Visual analog scale ( VAS ) straight line; a point has to be placed by the respondent. Different Scales: Different Answers? 10  Numeric rating scales ( NRS ) specific pre-determined points separated by equal interval. The respondent must choose from one of the points provided. Choi (2005); Hartman (2002); Pires (2011)

 Visual analog scale ( VAS ) Results:  the rating has to be measured afterwards  objectivizes patient´s perception Different Scales: Different Answers? 11  Numeric rating scales ( NRS ) Results:  influence the respondents answer by personal number preferences  less objective and precise Bousquet (2007); Price (1994); Rouve (2010); Schiavetti (1983)

Finding out how different scales, particularly VAS and NRS, can influence an answer Different Scales: Different Answers? 12  Advantages,  Disadvantages  Aplicability of VRS and NRS

Different Scales: Different Answers? 13 The differences between the structure and the use of these two scales. Validity Viability Reliability Reproducibility VAS or NRS ?

 Bousquet, P.J., et al., Visual analog scales can assess the severity of rhinitis graded according to ARIA guidelines. Allergy, (4): p  Choi, B.C. and A.W. Pak, A catalog of biases in questionnaires. Prev Chronic Dis, (1): p. A13.  Hartman, J.M., et al., Tutorials in clinical research: part IV: recognizing and controlling bias. Laryngoscope, (1): p  Hogikyan, N.D. and C.A. Rosen, A review of outcome measurements for voice disorders. Otolaryngol Head Neck Surg, (5): p  Pesudovs, K., et al., The development, assessment, and selection of questionnaires. Optometry and Vision Science, (8): p  Pires, M.D., G. Oliveira, and M. Behlau, Voice Activity and Participation Profile - VAPP administered in two different scales of response. J Soc Bras Fonoaudiol, (3): p  Price, D.D., et al., A comparison of pain measurement characteristics of mechanical visual analogue and simple numerical rating scales. Pain, (2): p  Rouve, S., et al., Numeric score and visual analog scale in assessing seasonal allergic rhinitis severity. Rhinology, (3): p  Schiavetti, N., et al., Direct magnitude estimation and interval scaling of stuttering severity. J Speech Hear Res, (4): p Different Scales: Different Answers? 14

 Ana Carvalho  Diana Castro  Fábio Gouveia  Inês Marques  Inês Farinha  Joana Cabrera Different Scales: Different Answers? 15  João Sousa  João Costa  Mariana Costa  Rita Pereira  Tânia Pereira

Introduction to Medicine I Class 6 Regent Teacher: Altamiro Costa Pereira Supervisor Teachers: Cristina da Costa Santos Gustavo Bacelar