Table 3. Multimorbidity prevalence using existing condition-lists and RR of multimorbidity when considering all 80 conditions (ceiling effect where adding additional conditions had little impact on prevalence).

Condition-list	No. of conditions in condition-list	Multimorbidity prevalence No. (%)	RR (95% CI)
All 80 conditions (reference)	80	473,533 (40.5)	1.0
Ho always + usually [10]	55	425,413 (36.4)	0.90 (0.89–0.90)
Barnett [16]	41	397,009 (34.0)	0.84 (0.83–0.84)
N’Goran [11]	29	219,098 (18.7)	0.46 (0.46–0.46)
Elixhauser [19]	28	268,261 (23.0)	0.57 (0.56–0.57)
Fortin [9]	27	389,286 (33.3)	0.82 (0.82–0.82)
Ho always [10]	27	129,698 (11.1)	0.27 (0.27–0.27)
Charlson [18]	21	135,166 (11.6)	0.28 (0.28–0.29)
Diederichs [6]	18	224,001 (19.2)	0.47 (0.47–0.47)
Salive [17]	14	222,859 (19.1)	0.47 (0.47–0.47)

RR, relative risk.