Table 3.

Instruments used to measure psychosis.

Nr	Instrument, Author	Items/Time/Formats	Domains assessed	Reliability	Validity
1	PANNS (Kay, Fiszbein & Opler, 1988) 5 studies: Perona-Garcelan et al., 2008, 2012; Wright et al., 2020; Rosen et al., 2017; Longden et al., 2020	30 items Positive scale items (7) Negative scale items (7) General psychopathology scale items (16) observations from interview/verbal report/information from care givers Time: 1 hour Response: PANNS rating anchors 1-7 (absent to extreme)	Psychotic symptoms: positive symptoms (delusions, grandiosity suspiciousness/persecution, unusual thought content) negative symptoms (blunted affect, emotional withdrawal, poor rapport, passive/apathetic social withdrawal, lack of spontaneity and flow of conversation, active social avoidance	Reported: Rosen et al.,2017 Internal consistency α = 0.77 – 0.89 Test-retest reliability r=0.80 Inter-rater reliability – Kappa = 0.85 Not reported: Perona-Garcelan et al., 2008, 2012; Wright et al., 2020; Longden et al., 2020	Not reported by any of the 5 studies
2	PSYRATS (Haddock et al., 1999) 4 studies: Kumar et al., 2018; Ubeda-Gomez et al., 2015; Perivoliotis et al., 2009; Farrelly et al., 2016	Interviewer -scored 2 subscales: hallucinations subscale (11 items); delusions subscale (6 items) Response: 5-point Likert-type scale (0 ‘not present’ -4’present continuously’)	Measures various dimensions (presence, typology, beliefs/conviction, distress and disruption associated) of delusions and auditory hallucinations	Reported: Ubeda-Gomez et al., 2015 Inter-rater reliability 0.80 Not reported: Kumar et al., 2018; Perivoliotis et al., 2009; Farrelly et al., 2016	Not reported by any of the 4 studies
3	SCID (First et al., 2002) 1 study: Rosen et al., 2017	Structured clinical interview for the DSM Response: 3 point scale (1- absent; 2- subthreshold; 3 – threshold or true present)	Psychopathological assessments of types of hallucinations and forms of delusions	Inter-rater reliability Kappa 0.83	Not reported
4	SANS (Andreasen, 1984) 1 study: Perivoliotis et al., 2009	25 items Interviewer-scored scale	Negative symptoms of schizophrenia	Not reported	Not reported
5	BAVQ-R (Chadwick et al., 2000) 1 study: Perivoliotis et al., 2009	Not described	Auditory hallucinations	Not reported	Not reported
6	PDI (Peters et al., 2004) 1 study: Humpston et al., 2016	21 item- scale	Delusional ideation	Cronbach’s alpha 0.77	Not reported
7	CAPS (bell, Halligan & Ellis, 2006) 1 study: Humpston et al., 2016	32 items- scale Subscales: Distress, intrusiveness, frequency	Anomalous perceptual experiences psychosis-like	Cronbach’s alpha 0.87	Good construct validity