Development of Flood Preparedness Behavior Scale: A Methodological Validity and Reliability Study.

Background: Floods are the most frequent natural disasters with a significant share of their mortality. Preparedness is capable of decreasing the mortality of floods by at least 50%. This paper aims to present the psychometric properties of a scale developed to evaluate the behavior of preparedness to floods in Sudan and similar settings.

Methods: In this methodological scale development study, experts assessed the content validity of the items of the developed scale. Data were collected from key persons of 413 households living in neighborhoods affected by the 2018 floods in Kassala City in Sudan. A pre-tested questionnaire of sociodemographic data and the Flood Preparedness Behavior Scale (FPBS) were distributed to the participants' houses and recollected. Construct validity of the scale was checked using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Internal consistency of the scale was checked using Cronbach's alpha. Test-retest reliability was assessed by Pearson's correlation coefficient. Item analyses and tests of significance of the difference in the mean scores of the highest and lowest score groups were carried out to ensure discriminatory power of the scale items.

Results: Experts agreed on the scale items. Construct validity of the scale was achieved using EFA by removing 34 items and retaining 25 items that were structured in three factors, named as: measures to be done before, during, and after a flood. Confirmatory factor analysis confirmed the construct obtained by EFA. The loadings of the items on their factors in both EFA and CFA were all > 0.3 with significant associations and acceptable fit indices obtained from CFA. The three factors were found to be reliable in terms of internal consistency (Cronbach's alpha coefficients for all factors were > 0.7) and test-retest reliability coefficient. In item analysis, the corrected total item correlations for all the items were > 0.3, and significant differences in the means of the highest and lowest score groups indicated good item discrimination power.

Conclusion: The developed 25 items scale is an instrument which produces valid and reliable measures of preparedness behavior for floods in Sudan and similar settings.