Quartile | Number of prescriptions | Potentially inappropriate prescribing | ||||||
---|---|---|---|---|---|---|---|---|
Mean (SD) | P-valuea | IRR (95% CI)b | P-valueb | Mean (SD) | P value a | IRR (95% CI)b | P-valueb | |
Usual Provider of Care Index | ||||||||
Lowest quartile | 9.67 (5.31) | — | ref | — | 2.50 (2.28) | — | ref | — |
Low intermediate quartile | 9.47 (5.17) | 0.20 | 0.99 (0.96 to 1.01) | 0.33 | 2.47 (2.18) | 1.00 | 1.00 (0.95 to 1.04) | 0.89 |
High intermediate quartile | 8.98 (4.93) | <0.01 | 0.97 (0.94 to 0.99) | 0.01 | 2.29 (2.17) | <0.01 | 0.96 (0.92 to 1.01) | 0.09 |
High quartile | 8.52 (4.75) | <0.01 | 0.96 (0.93 to 0.98) | <0.01 | 2.09 (2.06) | <0.01 | 0.93 (0.88 to 0.97) | <0.01 |
Bice–Boxerman Continuity of Care Index | ||||||||
Lowest quartile | 9.35 (5.23) | — | ref | — | 2.40 (2.23) | — | ref | — |
Low intermediate quartile | 9.29 (5.08) | 0.56 | 0.98 (0.95 to 1.01) | 0.11 | 2.41 (2.22) | 0.71 | 0.99 (0.94 to 1.04) | 0.60 |
High intermediate quartile | 9.47 (5.12) | 0.36 | 0.98 (0.96 to 1.01) | 0.13 | 2.44 (2.19) | 0.25 | 0.98 (0.93 to 1.03) | 0.41 |
High quartile | 8.56 (4.77) | <0.01 | 0.96 (0.93 to 0.99) | <0.01 | 2.09 (2.06) | <0.01 | 0.93 (0.88 to 0.97) | <0.01 |
Sequential Continuity Index | ||||||||
Lowest quartile | 9.10 (5.10) | — | ref | — | 2.30 (2.20) | — | ref | — |
Low intermediate quartile | 9.70 (5.15) | <0.01 | 0.98 (0.95 to 1.00) | 0.11 | 2.56 (2.22) | <0.01 | 0.99 (0.95 to 1.04) | 0.80 |
High intermediate quartile | 9.36 (5.22) | 0.12 | 0.98 (0.96 to 1.01) | 0.15 | 2.41 (2.20) | 0.04 | 0.98 (0.93 to 1.02) | 0.33 |
High quartile | 8.51 (4.71) | <0.01 | 0.96 (0.93 to 0.98) | <0.01 | 2.08 (2.07) | <0.01 | 0.93 (0.89 to 0.98) | <0.01 |
↵a Two-sided student t-test.
↵b IRRs estimated using negative binomial regression model, stratified by quartile of CGPC and adjusted for age, sex, 14 comorbidities, and frailty status. CGPC = continuity of GP care. CI = confidence interval. IRR = incidence rate ratio. ref = reference. SD = standard deviation.