Psychometric Properties of the Modified Family Affluence Scale (FAS II) among Adolescents in Nigeria: A Preliminary Report.

Objective: Social inequalities have serious health consequences for the developing child. Measuring these disparities is challenging, and the Family Affluence Scale (version II), a proxy indicator based on material wealth, was developed as a solution. However, it has not been validated for use in Sub-Saharan Africa and may not be applicable in developing countries. This preliminary study aimed to determine the convergent validity and reliability of a culturally adapted version of the FAS II.

Methods: A cross-sectional study was carried out among 422 senior secondary school students in Calabar, Nigeria. Modified versions of the Family Affluence Scale Version II (FAS II) were tested for their psychometric properties as proxy measures of socioeconomic status among Nigerian adolescents. Cronbach's alpha was computed as a measure of internal consistency, while Spearman's rank correlation and regression analysis were done to assess convergent validity.

Results: The mean sample age was 14.95 (±1.53) years, with an approximately equal gender distribution. Internal consistency was 0.68 for the 4-item version of the modified scale and increased to 0.75 when the item about travelling abroad was deleted. The modified FAS II scores (4 items) had a significant positive correlation with tuition cost (r=0.48, p<0.001), paternal educational attainment (r=0.27, p<0.001), and maternal educational attainment (r=0.30, p<0.001). Similarly, the 3-item version had a significant positive correlation with tuition cost (r=0.52, p<0.001), paternal educational attainment (r=0.24, p<0.001), and maternal educational attainment (r=0.30, p<0.001). Moderate (aOR: 4.25; 95%CI 2.45-7.39) and high affluence (aOR: 11.43; 95%CI 6.36-20.55) predicted attending more expensive schools. Moderate affluence (aOR: 2.15; 95%CI 1.28-3.62) and high affluence (aOR: 5.21; 95%CI 2.76-9.84) predicted a higher paternal education. Also, moderate affluence (aOR: 2.18; 95%CI 1.31-3.63) and high affluence (aOR: 7.42; 95%CI 3.76-14.66) predicted higher maternal education. The 3-item version performed similarly in terms of its predictive ability.

Conclusion: The modified version of the FAS II appears to have sufficient validity and reliability for measuring the socio-economic status of adolescents in Nigeria.