Validation of family impact scale to assess oral health-related quality of life in parents of Chilean preschoolers

Introduction
Health-related quality of life results from the perspective that well-being of patients is an important point considered in their treatment. From the 1960s, research and data collection with surveys began with the creation of multiple measurement tools for estimation of subjective opinions in a population. However, these tools must be translated into native language of a country of interest, and it also requires a correct validation by obtaining appropriate psychometric properties. OBJECTIVES: To assess the validity of Family Impact Scale (FIS) in parents of Chilean preschoolers living in the province of Concepción, Chile.

Material and methods
Target group was parents of preschoolers in the province of Concepción. Variables included oral health-related quality of life (OHRQoL) measured using Early Childhood Oral Health Impact Scale (ECOHIS) and FIS, oral hygiene, caries history, dental service utilization, sex, children’s age, parent’s age, and parent’s education level. Moreover, psychometric properties with internal consistency, temporal stability, criterion, and discriminative validity were evaluated. Cronbach’s α was estimated for internal consistency, and the following statistics were generated: intra-class correlation coefficient (ICC) for temporal stability, and Pearson’s r correlation coefficient for criterion and discriminative validity (p < 0.05).

Results
Regarding internal consistency, FIS presented a global Cronbach’s α of 0.765, being acceptable. For the temporal stability, an ICC of 0.99 (p < 0.001) was found, which indicated excellent temporal stability. For the criterion validity, moderate correlations (0.6 < Pearson’s r > 0.3) were found between FIS and ECOHIS as well as for most of the dimensions.

Conclusions
The Chilean version of the family impact scale exhibits questionable reliability and validity, despite its’ excellent temporal stability. Therefore, it is not recommended to use FIS in parents of Chilean preschoolers.