Addressing Missing Paternal Linkage in Administrative Data -- A Candidate Father Approach

IntroductionPaternal linkages are often missing from administrative health data, posing a challenge for familial health research. We propose and evaluate an approach to identify candidate fathers using residence and demographic information. MethodsWe conducted a population-based cohort study of Manitoba (Canada) adults between 1977 and 2017. We modelled the probability of missing paternal linkage and applied it to remove fathers for offspring with highest predicted probability (10%-50% missing linkages) in pre-1980 births, when missing paternal linkage was lowest. Candidate fathers were identified within the same postal code; up to three were randomly selected using parental age gap weights. We quantified the percentage of candidate sets containing the true father and estimated hazard ratios (HR) for paternal transfer of mental disorders and ischaemic heart disease (IHD) using true versus candidate fathers. Risk estimates were compared with indicator category and complete-case approaches. ResultsThe cohort included 140,001 offspring; 25.8% had missing paternal linkages. In the pre-1980 cohort, 27-28% of candidate sets included the true father. Using true fathers, paternal history was associated with mental disorders (HR 1.27, 95% CI 1.23-1.31) and IHD (HR 1.94, 95% CI 1.35-2.79). Using candidate fathers, associations were attenuated, with HRs ranging from 1.17 (95% CI 1.13-1.22) to 1.24 (95% CI 1.20-1.29) for mental disorders and 1.64 (95% CI 0.92-2.89) to 1.91 (95% CI 1.32-2.75) for IHD. Indicator category and complete-case approaches produced estimates close to the true association for mental disorders but deviated for IHD as paternal missingness increased. In the full cohort, estimates were similar for candidate father, indicator category, and complete-case approaches for both outcomes. ConclusionsAlthough the candidate father approach had low accuracy in identifying true fathers, it produced attenuated yet comparable risk estimates, particularly at low levels of missing paternal linkage, suggesting utility for familial research.