Evaluation of the Family Impact Scale for use in Brazil

The objectives of this study were to assess the validity and reliability of the Family Impact Scale (FIS) applied in Brazilian parents after translations and cultural adaptations to Brazilian Portuguese language and to evaluate the nature and extent to which the family functioning is compromised by the child oral conditions.

Parents were recruited from general populations for pre-testing (n=20), validity (n=210) and test-retest reliability (n=20) studies. The children were examined for dental caries, gingivitis, fluorosis and malocclusion.

The FIS discriminated among the categories of malocclusion and showed good construct validity. The Cronbach's alpha and intraclass correlation coefficients were 0.87 and 0.90, respectively. Almost 20% of the informants reported some family impact ;sometimes' or ;often/everyday' from the child's oral condition. Impact on FIS domains of this frequency ranged from 13.8% for financial difficulties to 24.4% for parental or family activities.

The Brazilian Portuguese version of FIS is valid and reliable. The results suggest that child oral conditions have a negative impact on the family. Further research is required, as these findings were based on cross-sectional study and convenience samples.