Health status assessment through scales and questionnaires: an important tool in Public Health

Building and evaluating scales as a tool in Public Health

  • Ilka Martins Rosa ACES BAIXO VOUGA
  • Rachel Valois
  • Gustavo Monteiro
  • Lara Guedes
Keywords: Surveys and Questionnaires, Public Health, Principal Component Analysis, Epidemiologic Studies, Mental Health


The development of measurement instruments is an important tool in epidemiological studies. During the preparation of a scientific study protocol, the collection of information is an important step in the research plan. When constructing questionnaires, mastering some concepts is fundamental, such as defining construct, domains, items, and index. How to select the content of the questionnaire? How to write a good question in the questionnaire? And what is the format of the answers? Is it ordinal? Is it Likert answers format? This extended abstract tries to demystify and clarify the important steps to be able to perform a straight-forward statistical evaluation of a questionnaire. There are important guidelines on how to construct and evaluate a scale-type instrument. It provides the tools to assess whether it has accuracy, validity and reliability. The example discussed here is in Mental Health (the presumed construct). An attempt is made to develop a scale with the domains Stress (S) and Eating Disorders (ED). If the two domains are related enough to each other, this hypothetical scale is able to represent the construct mental health. The questions for domain S were adapted from the original SF-36 scale; and for ED, from the EDE-A scale. This manuscript clarifies the important sections of a questionnaire: sociodemographic data; items for the domains S and ED; items to test criterion and construct validity; finally, the informed consent. Statistical analysis was performed in SPSS-28, with a significance level of 5%. The objective is to guide how to make and evaluate scale as a tool in epidemiological studies.

How to Cite
Rosa, I., Valois, R., Monteiro, G., & Guedes, L. (2022). Health status assessment through scales and questionnaires: an important tool in Public Health. Journal of Statistics on Health Decision, 4(1), 96-100.