Table 2.

Regression analysis of difference in means of consultation characteristics between PDDR groups, controlling for GP clustering

	Relationship	Crude difference in means (95% CI)	P-value	Adjusted for age of participants (95% CI)	P-value	Adjusted for participant factors (95% CI)a	P-value	Adjusted for GP factors (95% CI)b	P-value	Adjusted for all confounders (95% CI)c	P-value
Consult length, seconds
	Shallow	Reference		Reference		Reference		Reference		Reference
	Moderate	24 (−89 to 136)	0.05	−4 (−107 to 100)	0.49	−4 (−108 to 100)	0.51	4 (−101,109)	0.15	−15 (−119 to 90)	0.54
	Deep	118 (1 to 236)		58 (−57 to 173)		57 (−59 to 172)		99 (−14 to 211)		46 (−70 to 161)
Number of problems
	Shallow	Reference		Reference		Reference		Reference		Reference
	Moderate	0.2 (−0.3 to 0.6)	0.02	0.1 (−0.3 to 0.5)	0.34	0.1 (−0.3 to 0.5)	0.36	0.2 (−0.3 to 0.6)	0.06	0.1 (−0.3 to 0.5)	0.48
	Deep	0.5 (0.1 to 0.8)		0.3 (−0.1 to 0.8)		0.3 (−0.1 to 0.8)		0.5 (0.1 to 1)		0.3 (−0.2 to 0.8)
Number of issues
	Shallow	Reference		Reference		Reference		Reference		Reference
	Moderate	0.2 (−0.5 to 0.8)	0.01	0.1 (−0.5 to 0.8)	0.14	0.1 (−0.5 to 0.8)	0.14	0.2 (−0.5 to 0.9)	0.02	0.1 (−0.6 to 0.7)	0.22
	Deep	1 (0.2 to 1.7)		0.7 (0 to 1.5)		0.7 (0 to 1.5)		0.9 (0.2 to 1.7)		0.6 (−0.1 to 1.4)

^aAdjusted for age and sex of participants, and deprivation area of practice.

^bAdjusted for GP’s age, sex of participants, and years worked at the practice.

^cAdjusted for age and sex of participants, deprivation area of practice, GP’s age, sex, and years worked at the practice. OR = odds ratio. PDDR = Patient–Doctor Depth of Relationship.