Oral Presentation Australian Epidemiology Association ASM 2018

Regular General Practitioner contact – methods for measurement using administrative data (#44)

David Youens 1 , Mark Harris 1 , Suzanne Robinson 1 , David Preen 2 , Rachael Moorin 1
  1. Curtin University, Bentley, WA, Australia
  2. School of Population and Global Health, The University of Western Australia, Crawley, WA, Australia

Background

A small body of literature examines the relationship between “regularity” of contact with General Practitioners (GPs), i.e. the pattern of visits over time, and health outcomes. Methods previously used to may be conflated with the number of GP visits (frequency) which may impact on effect estimates.

Aim

Two published regularity measures, one derived from the variance in the days between GP visits and the second a categorical indicator, were assessed alongside a new measure designed to be uncorrelated with frequency.

Methods

A West Australian cohort at risk of diabetes-related hospitalisation was identified from primary care and hospitalisation data. Associations between regularity and frequency were assessed for each measure. Hospitalisation outcomes were regressed on regularity scores using negative binomial models, with and without frequency included, to assess whether associations between regularity and frequency biased estimates.

Results

The new index showed a weaker association between regularity and frequency than the previously published indices. According to the new measure, more regular GP contact was associated with a reduction in hospitalisation and this relationship was unchanged by the inclusion of frequency as a covariate. Under the existing measures regular contact was also associated with reduced hospitalisation, but this changed depending on the inclusion of frequency, suggesting that associations between regularity and frequency may confound relationships with health outcomes if uncontrolled.

Conclusion

This is the first work to compare measures of regularity and represents an important methodological advancement. Researchers should consider regularity of contact as a dimension of continuity of care when designing studies.