Ramperti 2010.

Study characteristics
Patient sampling	Prospective, consecutive.
Patient characteristics and setting	N included in study: 158. N in analysis: 158. Age: Mean 31.9 years (SD 11.2) Gender: M 99, F 59. Ethnicity: Not reported. Comorbid disorders: History of cannabis n = 14. Duration of symptoms: Not reported. Concurrent medications used: Not reported. Inclusion criteria: Between 16 and 65 years old, experiencing first episode of psychosis (affective and non‐affective). Current or previous history of alcohol and drug misuse were included. First episode of psychosis as the presence of any psychotic symptom for the first time in a person's life. Exclusion criteria: Organic brain disease and/or the patient being on antipsychotic medication for more than 30 days. Study aim: To establish the prevalence of FRS across the range of psychotic illnesses. Previous treatment for schizophrenia: No previous treatment. Clinical setting: Inpatients and outpatients. Country: Ireland.
Index tests	Description of FRS used: FRS consistent with those described by Mellor. Of these 11 items, 8 are represented in the SAPS (made feelings, impulses, and volitions are scored together). Symptoms in the SAPS are scored in a Likert Scale from "Not at all" to "severe" (0‐5). It was agreed between the assessors that due to the bizarre quality of the FRS ("questionable") should be used as a cut off point. The following 3 symptoms were not included as they are not clearly assessed in the SAPS or SCID: "audible thoughts," "Influence playing on the body or somatic passivity," and "delusional perception." Professionals performing test: Clinical fellows trained in the different rating scales. Resolution of discrepancies: Not reported. Inter‐rater reliability was achieved for the SAPS and SANS (kappa >0.7). The concordance for the SCID interview diagnosis ranged from 93% to 100% among raters. How FRS used in study: Prevalence.
Target condition and reference standard(s)	Reference standard: DSM‐IV. Target condition(s): Schizophrenia, schizophreniform disorder, and schizoaffective disorder (1 case) were combined together to form a schizophrenia spectrum group. Professionals performing test: Clinical fellows trained in the different rating scales. Resolution of discrepancies: Not reported. The concordance for the SCID interview diagnosis ranged from 93% to 100% among raters.
Flow and timing	Study process: Patients were contacted within 72 hours after the referral. All patients were assessed and diagnosed using the SCID‐Il. FRS were rated accordingly to the Scale for the Assessment of Positive Symptoms (SAPS). Clinical fellows trained in the different rating scales carried out the assessments. Diagnoses made using the DSM‐IV. Unclear when the tests were applied and the order. Follow‐up: Not reported. Exclusions: Not explicitly reported.
Comparative
Notes
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Yes
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?	Unclear
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?	Unclear
		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?	Unclear
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