The effect of continuity of care on medical costs in patients with chronic shoulder pain.

Unnecessary surgery could be prevented through continuity of care (COC). The present study aimed to investigate the relationships between COC, surgery and cost associated with chronic shoulder pain. We used the Health Insurance Review and Assessment Service national patient sample (HIRA-NPS) in 2017. A total of 1717 patients were included. Bice-Boxerman Continuity of Care Index was used as the indicator for measuring the COC. Occurrence of surgery, associated costs, and direct medical costs were analysed. Logistic regression, a two-part model with recycled predictions and generalized linear model with gamma distribution were used. The majority of patients were 40-65 years old (high COC: 68.4%; low COC: 64.4%). The odds ratio (OR) for surgery was 0.41 in the high-COC group compared to the low COC group (95% CI, 0.20 to 0.84). Direct medical cost was 14.09% (95% CI, 8.12% to 19.66%) and 58.00% lower in surgery cost (95% CI, 57.95 to 58.05) in the high-COC group. Interaction with COC and shoulder impingement syndrome was significant lower in direct medical cost (15.05% [95% CI, 1.81% to 26.51%]). High COC was associated with low medical cost in patients diagnosed with chronic shoulder pain.