Summary of findings for the main comparison. Altered length compared to usual length for increasing the length of primary care physicians' consultations.

Altered length compared to usual length for increasing the length of primary care physicians' consultations
Patient or population: primary care physicians Setting: UK Intervention: increase or decrease in consultation length Comparison: routine consultation length
Outcomes	Impact	№ of participants (studies)	Certainty of the evidence (GRADE)
Provider performance ‐ length of consultation	It is uncertain whether altering the length of consultations increases the length of primary care physicians’ consultations In all trials the difference in consultation length was less than the change in appointment length, particularly when appointment length was extended	23 primary care physicians (3 observational studies)	⊕⊝⊝⊝ Very low 1, 2
Provider performance ‐ referrals	It is uncertain whether altering the length of consultations increases primary care physicians’ referrals The 2 trials assessing the percentage of consultations resulting in specialist referrals found similar results for all groups, although rates were slightly higher with longer appointments	21 primary care physicians (2 observational studies)	⊕⊝⊝⊝ Very low 1, 2
Provider performance ‐ examinations	It is uncertain whether altering the length of consultations increases primary care physicians’ examinations 3 trials assessed the percentage of consultations in which 1 or more physical examinations took place	23 primary care physicians (3 observational studies)	⊕⊝⊝⊝ Very low 1, 2
Provider performance ‐ prescriptions	It is uncertain whether altering the length of consultations increases primary care physicians’ prescriptions 3 trials assessed the percentage of consultations in which prescriptions were issued	23 primary care physicians (3 observational studies)	⊕⊝⊝⊝ Very low 1, 2
Patient satisfaction	It is uncertain whether altering the length of consultations increases patient satisfaction 4 trials assessed patient satisfaction with the care received, none of which used a validated instrument	43 primary care physicians (4 observational studies)	⊕⊝⊝⊝ Very low 1, 2,3
Resources ‐ not measured	No studies reported on the effect of altering the length of consultations on resources	(0 studies)	‐
GRADE Working Group grades of evidence High certainty: We are very confident that the true effect lies close to that of the estimate of the effect Moderate certainty: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low certainty: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low certainty: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect

¹Downgraded 1 point due to high risk of bias (allocation and selective sampling).
 ²Downgraded 1 point due to small sample size.
 ³Downgraded 1 point due to non‐validated assessment (surrogate outcome).