RESUMEN
AIMS: Adverse childhood experiences are known to relate positively to various health risks and adverse health behaviour in adult life, although the precise mechanisms are still debated. The aim of this study was to investigate whether a single-item measure of the quality of childhood relationships with family and household members might show a similar association. METHODS: We measured the overall quality of relationships with family and household members during the first 18 years of life. A one-dimensional question scored 0-10 (N=4983) was included in the ongoing SIBS Iceland Patient Association's national 'Life and Health' public health prevention project among adults. Relationship quality was then assessed against measures of health and health behaviour using 21 validated scales. RESULTS: A lower childhood relationships score was associated with a higher risk of all 21 suboptimal health and health behaviour outcomes in adulthood, with adjusted effect sizes measured by standardised betas (magnitude 0.111-0.284), variance explained (1.3-8.5%) and per-point adjusted odds ratios (1.10-1.30). The strongest associations were found with measures of social and mental health, followed by physical health, alcohol and tobacco use, sleeping problems, financial sustenance, physical pain and aerobic fitness. CONCLUSIONS: Odds were found to match well with pooled odds ratios presented in a systematic review of 37 adverse childhood experiences studies. This may indicate that a one-dimensional relationships question is a useful substitute in surveys in which a traditional multi-question adverse childhood experiences scale cannot be accommodated. Further investigations are recommended to investigate the applicability of a single adverse childhood experiences question.