2.1. Study design
This experimental field trial is part of a comprehensive study with three phases of intervention development, implementation, and evaluation. The study design was based on the IM approach. First introduced in 1998 by Bartholomew et al., IM comprises six steps, as follows: (1) needs assessment, (2) creating change goals matrix, (3) theory-based operational solutions, (4) program design, (5) program acceptance and implementation, and (6) program evaluation (Phase 1, needs assessment and the first step of the IM, consisted of three sub-studies. In sub-study 1, the FNLIT questionnaire previously designed by Doustmohammadian et al. (The study followed the CONSORT guideline for the design and reporting of clinical trials (S1 CONSORT Checklist), and the CONSORT flow diagram for the study is shown in CONSORT flow diagram.