Table 1.

Characteristics of Included General Population-based Prospective Studies of CRP and Psychosis.

Study	Country	Cohort	Mean (SD) age at baseline (at blood sampling), yrs	Mean (SD) age at follow-up (at psychosis diagnosis), yrs	Mean (SD) time to follow-up, yrs	Male sex (%)	White ethnicity (%)	Method of case ascertainment	Definition of outcome	Total analytic sample (N)	N of Incident cases of psychosis at follow-up (N of cases with CRP > 3 mg/L)	Analytic sample excluding CRP > 10 mg/L (N)	Incident cases of psychosis at follow-up excluding CRP > 10 mg/L (N)
Wium-Andersen et al.28	Denmark	Copenhagen City Heart Study and Copenhagen General Population Study	57 (13.7)	64.3 (14.0)	5.25 (4.10)	44.5	100	Hospital-based diagnoses from the national Danish Patient and the Causes of Death Registry and out-patient and emergency contacts.	Psychotic disorders according to ICD-8 (295.0-9, 296.89, 297, 298.39, and 301.83) or ICD-10 (F20.0-9, F21-F29).	78,769	131 (49)	75,989	116
Metcalf et al.31	Finland	Northern Finland Birth Cohort 1986	16.00 (0.38)	26.92 (0.87)	10.92 (0.85)	49.9	100a	Healthcare-based diagnoses from the Finnish Hospital Discharge Register and healthcare outpatient and hospital outpatient records. Inpatient and community	Non-affective psychotic disorders according to ICD-10 (F20–F29)	6,362	88 (9)	6,258	83
Laukkanen et al.30	Finland	Kuopio Ischaemic Heart Disease cohort	53.1 (5.1)	78 (5.1)	21.5 (7.6)	100	100	An independent committee of researchers reviewed all potential cases and assigned diagnoses. Inpatient and community	Psychotic disorders according to ICD-9 (290–299) and ICD-10 (F00–F09 and F20–F29).	2,552	245 (54)	2,463	238
Perry et al.34	England	ALSPAC birth cohort	9.9 (0.32)	24.04 (0.85)	15 (not available)	46.2	98.7	Face-to-face semi-structured Psychosis-Like Symptom Interview (PLIKSi) of entire cohort attending clinical assessment	Psychotic disorderb	2,224	30 (2)	2,203	30

^aTo the Northern Finland Birth Cohort (NFBC) 1986 research team’s knowledge, participants are mostly, if not all, of Finnish origin and white ethnicity. However, there has been no official documentation of race or ethnicity in the cohort, so 100% white ethnicity and Finnish origin is an assumption (Minna Ruddock, PhD, NFBC1986 research director, email communication, 13 July 2020).

^bIn Perry et al., cases of psychotic disorder were defined as having interviewer-rated definite psychotic episodes (PEs) that were not attributable to the effects of sleep/fever, had occurred regularly at least once per month over the previous 6 months, and were either (i) very distressing, (ii) negatively impacted social/occupational functioning, or (iii) led to help-seeking from a professional source. PEs were identified through the face-to-face, semi-structured Psychosis-Like Symptom Interview (PLIKSi) conducted by trained psychology graduates and were coded according to the definitions in the Schedules for Clinical Assessment in Neuropsychiatry, Version 2.0. PEs, occurring in the last 6 months, covering the three main domains of positive psychotic symptoms were elicited: hallucinations, delusions, and thought interference (as per Sullivan et al.⁶⁵).