Development and validation of an instrument designed to measure factors influencing physician prescribing decisions

BACKGROUND: Previous attempts to develop an instrument to measure factors that influence prescribing decisions among physicians were relatively insufficient and lacked validation scale. OBJECTIVE: We present a new tool that attempts to address this shortcoming. Hence, this study aims to develop and validate a self-administrated instrument to explain factors that influence the prescribing decisions of physicians. METHODS: The questionnaire was developed based on literature and then subjected to an exhaustive assessment by a board of professionals and a pilot examination before being administered to 705 physicians. Three pre-tests were carried out to evaluate the quality of the survey items. In pre-test 1, after items are generated and the validity of their content is assessed by academics and physicians. In pre-test 2, the scale is carried out with a small sample of 20 respondents of physicians. In pre-test 3, fifty drop-off questionnaires were piloted amongst physicians to test the reliability. RESULTS: On the basis of partial least squares structural equation modelling (PLS-SEM) analyses using SmartPLS 3, the content and convergent validity of the instrument were confirmed with 44 items grouped into four categories, namely, marketing efforts, patient characteristics, pharmacist variables, and contextual factors with 13 reflective constructs. CONCLUSIONS: The study outcomes prove that the scale is more valid and reliable for measuring factors that influence the decision of the physician to prescribe the drug. The development and presentation of a scale of thirteen factors related to physicians prescribing decisions help to ensure valid findings and facilitates comparisons of studies and research settings.