Appendix Table 3. Probability of primary care patients changing their source of primary care by time elapsed since their visit to their last provider, stratified by year of entry cohort and disease diagnosis (diabetes or hypertension). Parentheses denote 95% confidence intervals.
Time elapsed since a patient’s visit to their last provider
Cohort Site of PC Visit 6 Months 12 Months 18 Months 24 Months 30 Months 36 Months
2012 Diabetes CHC 0.17
(0.15, 0.18) 0.37
(0.35, 0.39) 0.49
(0.46, 0.52) 0.56
(0.53, 0.59) 0.61
(0.58, 0.64) 0.63 (0.60, 0.66)
PC Clinic 0.32
(0.30, 0.33) 0.58
(0.57, 0.60) 0.69
(0.67, 0.71) 0.75
(0.73, 0.77) 0.79
(0.77, 0.81) 0.81 (0.79, 0.83) Multispecialty Clinic 0.20
(0.19, 0.22) 0.38
(0.35, 0.41) 0.50
(0.47, 0.53) 0.55
(0.52, 0.59) 0.60
(0.56, 0.63) 0.66 (0.62, 0.66) Single-PC practice 0.46
(0.43, 0.49) 0.67
(0.64, 0.70) 0.77
(0.74, 0.81) 0.81
(0.78, 0.84) 0.84
(0.81, 0.87) 0.86 (0.83, 0.89)
2013 Diabetes CHC 0.15
(0.14, 0.17)
0.36 (0.33, 0.38)
0.46 (0.43, 0.49)
0.53 (0.50, 0.56)
0.57 (0.54, 0.60)
0.61 (0.58, 0.65)
PC Clinic 0.20
(0.18, 0.21) 0.42
(0.40, 0.44) 0.55
(0.52, 0.58) 0.63
(0.60, 0.66) 0.68
(0.65, 0.70) 0.70 (0.67, 0.73) Multispecialty Clinic 0.23
(0.21, 0.25)
0.42 (0.39, 0.44)
0.51 (0.48, 0.55)
0.58 (0.54, 0.61)
0.63 (0.60, 0.67)
0.69 (0.66, 0.73) Single-PC practice 0.49
(0.45, 0.53) 0.71
(0.67, 0.75) 0.78
(0.74, 0.81) 0.83
(0.79, 0.86) 0.84
(0.80, 0.87) 0.86 (0.82, 0.89)
2014 Diabetes CHC 0.14
(0.12, 0.15) 0.33
(0.31, 0.35) 0.47
(0.44, 0.49) 0.57
(0.54, 0.60) 0.63
(0.59, 0.66) 0.66 (0.62, 0.69)
PC Clinic 0.21
(0.20, 0.22)
0.44 (0.42, 0.46)
0.56 (0.54, 0.59)
0.65 (0.62, 0.67)
0.69 (0.66, 0.72)
0.75 (0.72, 0.77) Multispecialty Clinic 0.25
(0.23, 0.27) 0.46
(0.43, 0.49) 0.58
(0.54, 0.61) 0.65
(0.62, 0.68) 0.70
(0.66, 0.73) 0.74 (0.71, 0.78) Single-PC practice 0.38
(0.34, 0.42)
0.64 (0.59, 0.69)
0.75 (0.69, 0.79)
0.81 (0.76, 0.86)
0.85 (0.80, 0.89)
0.86 (0.81, 0.90) 2012
Hypertension CHC 0.16
(0.15, 0.17) 0.35
(0.34, 0.37) 0.47
(0.45, 0.49) 0.55
(0.53, 0.57) 0.60
(0.58, 0.62) 0.63 (0.60, 0.65)
PC Clinic 0.30
(0.29, 0.31) 0.56
(0.55, 0.57) 0.69
(0.67, 0.70) 0.75
(0.73, 0.76) 0.78
(0.77, 0.80) 0.81 (0.79, 0.82) Multispecialty Clinic 0.21
(0.20, 0.22) 0.39
(0.37, 0.41) 0.50
(0.48, 0.53) 0.56
(0.54, 0.59) 0.61
(0.58, 0.63) 0.64 (0.61, 0.66) Single-PC practice 0.44
(0.42, 0.47) 0.66
(0.64, 0.69) 0.78
(0.75, 0.80) 0.82
(0.79, 0.84) 0.84
(0.82, 0.86) 0.86 (0.83, 0.88)
2013
Hypertension CHC 0.14
(0.13, 0.15) 0.30
(0.29, 0.32) 0.42
(0.40, 0.44) 0.49
(0.47, 0.51) 0.55
(0.52, 0.57) 0.60 (0.57, 0.62) Primary Care Clinic 0.19
(0.18, 0.20) 0.40
(0.38, 0.42) 0.54
(0.52, 0.56) 0.61
(0.59, 0.63) 0.65
(0.63, 0.67) 0.68 (0.66, 0.70)
PC Clinic 0.22
(0.21, 0.24) 0.42
(0.40, 0.44) 0.52
(0.50, 0.55) 0.59
(0.57, 0.61) 0.65
(0.62, 0.67) 0.70 (0.67, 0.72) Single-PC practice 0.46
(0.43, 0.49) 0.70
(0.67, 0.73) 0.79
(0.77, 0.82) 0.83
(0.81, 0.86) 0.86
(0.83, 0.88) 0.87 (0.84, 0.90) 2014
Hypertension CHC 0.13
(0.13, 0.14) 0.31
(0.30, 0.33) 0.45
(0.43, 0.47) 0.56
(0.54, 0.58) 0.62
(0.59, 0.64) 0.66 (0.63, 0.68)
PC Clinic 0.21
(0.20, 0.22) 0.42
(0.41, 0.44) 0.56
(0.55, 0.58) 0.64
(0.62, 0.66) 0.70
(0.68, 0.72) 0.74 (0.72, 0.76) Multispecialty Clinic 0.24
(0.24, 0.26) 0.45
(0.43, 0.47) 0.57
(0.54, 0.59) 0.65
(0.62, 0.67) 0.71
(0.68, 0.73) 0.75 (0.72, 0.77) Single-PC practice 0.37
(0.34, 0.40) 0.62
(0.58, 0.66) 0.72
(0.68, 0.75) 0.78
(0.74, 0.81) 0.80
(0.77, 0.84) 0.83 (0.79, 0.86) Note: DM, diabetes; HTN, hypertension. The probability of patients who changed provider was modeled using generalized estimating equation (GEE) logistic regression. As patients could have multiple gaps at a specified length (multiple gaps of 6 months or more between visits resulting in multiple observations per patient within each analysis), we used GEE models to account for within patient correlation using a robust sandwich variance estimator. GEE models included primary care provider type, cohort year, and the interaction term between those two terms. Odds ratios from GEE logistic models were transformed to estimate predicted probabilities of provider change having occurred. Models were stratified by the year in which the primary care visit starting the time interval occurred. Patients with both DM and HTN were included in both cohorts.