Tanenberg‐Karant 1995.

Study characteristics
Patient sampling	Prospective, unclear whether consecutive or random selection.
Patient characteristics and setting	N included in study: 196. N in analysis: 196. Age: Not reported. Gender: Not reported. Ethnicity: Not reported. Comorbid disorders: Not reported. Duration of symptoms: Not reported. Concurrent medications used: Not reported. Inclusion criteria: Aged 15 to 60 years. Experiencing first admission to inpatient facilities. Screened for the presence of psychotic symptoms. "This study focused on 196 hospitalized patients with a 6‐month longitudinal best‐estimate research diagnosis (see below) of schizophrenia, schizoaffective disorder, schizophreniform disorder, bipolar disorder with psychotic features, and major depressive disorder with psychotic features. Six additional patients in these diagnostic groups did not have delusions or hallucinations (i.e., they had, for example, thought disorder)." Exclusion criteria: First psychiatric hospitalisation more than 6 months before current admission, moderate or severe mental retardation, and non‐English‐speaking status. Study aim: To examine the prevalence and correlates of bizarre delusions and FRS in a first‐admission sample with psychosis. Previous treatment for schizophrenia: Not reported. Clinical setting: Inpatients. Country: USA.
Index tests	Description of FRS used: FRS evaluated using SCID interview, which included nine of 11 FRS delusions and hallucinations. It does not specifically ask about audible thoughts or delusional perception. These were only coded from information volunteered by the patient during the interview or mentioned by the clinician either in the discharge summary or the clinician interview.* FRS decisions were based on definitions and examples provided by Mellor. Professionals performing test: Two project psychiatrists blind to the best‐estimate diagnosis. Resolution of discrepancies: For all but eight disagreements, consensus between the two psychiatrists was achieved after discussion. The inter‐rater agreement between pairs of psychiatrists was k = 0.861 for FRS. How FRS used in study: Prevalence.
Target condition and reference standard(s)	Reference standard: 6‐month longitudinal best‐estimate research diagnosis based on DSM‐III‐R using SCID, discharge summaries, and other relevant information. Target condition(s): Schizophrenia, schizoaffective disorder, schizophreniform disorder, bipolar disorder with psychotic features, and major depressive disorder with psychotic features. Professionals performing test: Two project psychiatrists independently reviewed the SCIDs, discharge summaries, and other relevant information and arrived at a diagnosis. Each case was presented at a project psychiatrists' meeting and a best‐estimate diagnosis was determined. (SCID interviewers were master's‐level mental health professionals with considerable clinical experience and who were trained over a period of 3 to 6 months) Resolution of discrepancies: SCID: Not reported. Interrater reliability assessments were conducted on approximately every tenth interview, and mean K values for mood and psychosis sections were high. Diagnosis: Regardless of whether a consensus was reached by the two psychiatrists, each case was presented at a project psychiatrists' meeting and a best‐estimate diagnosis was determined.
Flow and timing	Study process: SCID interview at hospital before discharge and a 6‐month follow‐up interview typically took place in the patients' homes. After these interviews two psychiatrists reviewed the SCIDs, discharge summaries, and other relevant information and arrived at a diagnosis. Regardless of whether a consensus was reached by the two psychiatrists, each case was presented at a project psychiatrists' meeting and a best‐estimate diagnosis was determined. Follow‐up: 6 months. Exclusions: Not explicitly reported.
Comparative
Notes	*Determinations about delusions and hallucinations derive primarily from the interview, with supplementation from other informed sources (medical records, treating clinician, interview with significant other).
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
		Unclear	Low
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
Did the study pre‐specify whether they were using one or multiple FRSs?	No
		Unclear	High
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	No
		Unclear	High
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Were all patients included in the analysis?	Yes
Did all patients receive a reference standard?	Yes
Did all patients receive the same reference standard?	Yes
Did all patients receive an index test?	Yes
Did all patients receive the same index test?	Yes
		Low