School absence policy and healthcare use: a difference-in-difference cohort analysis.

Background: A national policy in Norway demanding certificates for medical absences in upper secondary school was implemented in 2016, leading to an increase in general practitioner (GP) visits in this age group.

Objectives: To assess the policy's effect on the use of primary and specialist healthcare.

Methods: A cohort study following all Norwegian youth aged 14-21 in the years 2010-2019 using a difference-in-differences approach comparing exposed cohorts expected to attend upper secondary school after the policy change in 2016 with previous unexposed cohorts. Data were collected from national registries.

Results: The absence policy led to the increased number of contacts with GPs for exposed cohorts during all exposed years, with estimated incidence rate ratios (IRRs) in the range from 1.14 (95% confidence intervals [CI] 1.11-1.18) to 1.25 (95% CI 1.21-1.30). Consultations for respiratory tract infections increased during exposed years. However, there was no conclusive policy-related difference in mental health consultations with GPs. In specialist healthcare we did not find conclusive evidence of an effect of absence policy on the risk of any contact per school year, but there was a slightly increased risk of contacts with ear-nose-throat specialist services.

Conclusions: We found an increase in general practice contacts attributable to the school absence policy. Apart from a possible increase in ear-nose-throat contacts, increased GP attention did not increase specialized healthcare.