Robust association between autistic traits and psychotic-like experiences in the adult general population: epidemiological study from the 2007 Adult Psychiatric Morbidity Survey and replication with the 2014 APMS.

BACKGROUND: Studies have shown that there are overlapping traits and symptoms between autism and psychosis but no study to date has addressed this association from an epidemiological approach in the adult general population. Furthermore, it is not clear whether autistic traits are associated with specific symptoms of psychosis or with psychosis in general. We assess these associations for the first time by using the Adult Psychiatric Morbidity Survey (APMS) 2007 and the APMS 2014, predicting an association between autistic traits and probable psychosis, and specific associations between autistic traits and paranoia and strange experiences. METHODS: Participants (N = 7353 in 2007 and 7500 in 2014) completed the Psychosis Screening Questionnaire (PSQ) and a 20-item version of the Autism Quotient (AQ-20). Binomial logistic regressions were performed using AQ-20 as the independent variable and probable psychosis and specific symptoms as dependent variables. RESULTS: In the APMS 2007 dataset, significant associations were found between autism traits and probable psychosis, paranoia, thought insertion, and strange experiences. These results were replicated in APMS 2014 but with the additional significant association between autistic traits and hallucinations. Participants in the highest quartile of the AQ-20, compared with the lowest quartile, had an increased risk of probable psychosis of odds ratio (OR) = 15.5 [95% confidence interval (CI) 4.57-52.6] in APMS 2007 and OR = 22.5 (95% CI 7.64-66.3) in APMS 2014. CONCLUSIONS: Autistic traits are strongly associated with probable psychosis and psychotic experiences with the exception of mania. Limitations such as the cross-sectional nature of the study are discussed.

A comparative study of the nature and magnitude of problems sleeping in inflammatory bowel disease (IBD) compared to healthy controls.

Inflammatory Bowel Disease (IBD) is commonly associated with poor global sleep quality, and has been posited as a modifiable determinant of IBD related outcomes. However, there is little evidence on the specific types of problems sleeping (e.g., sleep apnea, insomnia etc.) that might characterize the poor sleep quality experienced by those with IBD. The present research aimed to investigate the severity of seven specific types of problems sleeping in those with IBD vs. a healthy control group. This cross sectional comparison study recruited N = 409 with IBD, and N = 377 healthy controls. The Sleep-50 questionnaire was used to assess the presence of seven type of problems sleeping. Multivariate Analysis of Covariance (MANCOVA) was used to compare the severity of sleep disturbances between the IBD and control groups. Those in the IBD group reported significantly more severe experiences of five of the seven domains of the sleep-50, including increased; sleep apnea, insomnia, narcolepsy, restless-legs, and nightmares. More research is needed to; (i) improve the identification and treatment of problems sleeping in routine care; (ii) understand the mechamism(s) of action that links problems sleeping to IBD realted outcomes; and (iii) develop adapted interventions to improve sleep in those with IBD.

Relationships between paranoid thinking, self-esteem and the menstrual cycle.

This study aimed to investigate whether paranoid experiences and levels of self-esteem fluctuate over the menstrual cycle and whether levels of self-esteem are lower when perceived persecution is felt to be deserved. Measures of anxiety, depression, persecution, deservedness and self-esteem were completed on-line by 278 women over their menstrual cycle. Responses were compared at the paramenstrual (3 days before and after menses onset) and mid-cycle phase. At the paramenstrual phase persecution, negative self-esteem, anxiety and depression were higher and positive self-esteem was lower than at mid-cycle. A greater proportion of women experienced persecution as deserved at the paramenstrual phase. This was associated with higher depression and negative self-esteem scores. Increased levels of deservedness significantly strengthened the relationship between persecution and negative, but not positive, self-esteem. These findings suggest that the paramenstrual phase is a time of vulnerability to increased paranoid experiences, an increased likelihood that feelings of persecution will feel deserved and lowered self-esteem. The findings support the view that interpersonal sensitivities may be key to menstrual cycle symptoms and have an impact on relationships. Further, the study illustrated that ideas developed for psychosis could make a valuable contribution to understanding and managing this aspect of menstruation-related distress.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline.

This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). The Guideline was also reviewed and endorsed by the British Society of Gastroenterology (BSG). It addresses the roles of small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders. Main recommendations 1 ESGE recommends small-bowel video capsule endoscopy as the first-line investigation in patients with obscure gastrointestinal bleeding (strong recommendation, moderate quality evidence). 2 In patients with overt obscure gastrointestinal bleeding, ESGE recommends performing small-bowel capsule endoscopy as soon as possible after the bleeding episode, optimally within 14 days, in order to maximize the diagnostic yield (strong recommendation, moderate quality evidence). 3 ESGE does not recommend the routine performance of second-look endoscopy prior to small-bowel capsule endoscopy; however whether to perform second-look endoscopy before capsule endoscopy in patients with obscure gastrointestinal bleeding or iron-deficiency anaemia should be decided on a case-by-case basis (strong recommendation, low quality evidence). 4 In patients with positive findings at small-bowel capsule endoscopy, ESGE recommends device-assisted enteroscopy to confirm and possibly treat lesions identified by capsule endoscopy (strong recommendation, high quality evidence). 5 ESGE recommends ileocolonoscopy as the first endoscopic examination for investigating patients with suspected Crohn's disease (strong recommendation, high quality evidence). In patients with suspected Crohn's disease and negative ileocolonoscopy findings, ESGE recommends small-bowel capsule endoscopy as the initial diagnostic modality for investigating the small bowel, in the absence of obstructive symptoms or known stenosis (strong recommendation, moderate quality evidence).ESGE does not recommend routine small-bowel imaging or the use of the PillCam patency capsule prior to capsule endoscopy in these patients (strong recommendation, low quality evidence). In the presence of obstructive symptoms or known stenosis, ESGE recommends that dedicated small bowel cross-sectional imaging modalities such as magnetic resonance enterography/enteroclysis or computed tomography enterography/enteroclysis should be used first (strong recommendation, low quality evidence). 6 In patients with established Crohn's disease, based on ileocolonoscopy findings, ESGE recommends dedicated cross-sectional imaging for small-bowel evaluation since this has the potential to assess extent and location of any Crohn's disease lesions, to identify strictures, and to assess for extraluminal disease (strong recommendation, low quality evidence). In patients with unremarkable or nondiagnostic findings from such cross-sectional imaging of the small bowel, ESGE recommends small-bowel capsule endoscopy as a subsequent investigation, if deemed to influence patient management (strong recommendation, low quality evidence). When capsule endoscopy is indicated, ESGE recommends use of the PillCam patency capsule to confirm functional patency of the small bowel (strong recommendation, low quality evidence). 7 ESGE strongly recommends against the use of small-bowel capsule endoscopy for suspected coeliac disease but suggests that capsule endoscopy could be used in patients unwilling or unable to undergo conventional endoscopy (strong recommendation, low quality evidence).

A preliminary investigation into theory of mind and attributional style in adults with grandiose delusions.

INTRODUCTION: A preliminary cognitive model of grandiose delusions has been put forward suggesting that persecutory and grandiose delusions shared distinct, yet overlapping psychological processes. This study aims to test this model and hypothesises that participants experiencing grandiose delusions may demonstrate a theory of mind (ToM) impairment and differences in attributional style compared to a control group. METHODS: A cross-sectional design compared the performance of 18 individuals with grandiose delusions to a control group of 14 participants with depression. ToM was measured using a non-verbal joke appreciation task and a verbal stories task. Attributional style was measured using the internal, personal and situational attributions questionnaire. RESULTS: Participants experiencing grandiose delusions performed significantly worse on both ToM tasks compared to controls. Furthermore, these participants provided significantly more atypical answers when explaining the joke behind the ToM cartoons. No differences for subjective funniness ratings or attributional style were found. CONCLUSIONS: This preliminary study indicated participants experiencing grandiose delusions have ToM impairments which may contribute to the maintenance of this symptom.

Attributional style and theory of mind in people with Alzheimer disease and persecutory delusions.

OBJECTIVE: Between 7% and 40% of people with Alzheimer disease (AD) experience persecutory delusions (PDs) during the course of their dementia. Although attributional style and theory of mind processes have been linked with PDs in people with psychosis, they have not yet been examined in those with AD and PDs. The objective of this study was, hence, to explore the role of these cognitive processes in groups of participants with AD with and without PDs, as well as a nonclinical comparison group. METHOD: Measures of attributional style and theory of mind were administered to three groups: people with AD and PDs (n = 22), people with AD without PDs (n = 22), and a nonclinical group (n = 23). RESULTS: Although no clear differences in attributional style between the three groups were found, the group with AD and PDs were found to perform worse on the first-order (but not second-order) theory of mind task than the other two groups. CONCLUSIONS: Interventions designed to enhance theory of mind skills might be beneficial for individuals with AD and PDs.

Delusions and the dilemmas of life: A systematic review and meta-analyses of the global literature on the prevalence of delusional themes in clinical groups.

We investigated the prevalence of persecutory, grandiose, reference, control, and religious delusions in adult clinical populations worldwide and whether they differed according to country characteristics or age, gender, or year of publication. 123 studies met inclusion criteria, across 30 countries; 102 (115 samples, n = 20,979) were included in the main random-effects meta-analysis of studies measuring multiple delusional themes (21 in a separate analysis of studies in recording a single theme). Persecutory delusions were most common (pooled point estimate: 64.5%, CI = 60.6-68.3, k = 106, followed by reference (39.7%, CI 34.5-45.3, k = 65), grandiose (28.2, CI 24.8-31.9, k = 100), control 21.6%, CI 17.8-26.0, k = 53), and religious delusions 18.3%, CI 15.4-21.6, k = 50). Data from studies recording one theme were broadly consistent with these findings. There were no effects for study quality or publication date. Prevalences were higher in samples exclusively with psychotic patients but did not differ between developed and developing countries, or by country individualism, power distance, or prevalence of atheism. Religious and control delusions were more prevalent in countries with higher income inequality. We hypothesize that these delusional themes reflect universal human dilemmas and existential challenges.

Autistic women's experiences of self-compassion after receiving their diagnosis in adulthood.

LAY ABSTRACT: Knowledge of autistic individuals' experiences of self-compassion is very limited. This study investigated autistic women's experiences of self-compassion after receiving their diagnosis in adulthood. Eleven autistic women were interviewed about their experiences of receiving their diagnosis in adulthood and their experiences of self-compassion. Systematic analysis of the interview transcripts revealed common themes in the participants' experiences. Participants reported that their autism diagnosis helped them to better understand themselves, particularly when reflecting on problematic past experiences. After receiving an autism diagnosis, participants described being able to relate to themselves with greater self-kindness compared to previous self-criticism; this included allowing themselves to assert their needs and engage in self-care activities. Participants spoke about having difficult social experiences, including feeling pressure to conform to expectations in society and often feeling misunderstood. The findings highlight the barriers autistic women face obtaining their diagnoses and demonstrate the need for autism training for professionals to support early identification. Findings from this study suggest that interventions aimed at developing self-compassion could support and enhance autistic women's well-being.

More than words? Hypomanic personality traits, visual imagery and verbal thought in young adults.

The use of visual mental imagery has been proposed to be a risk factor for the development of bipolar disorder, due to its potential to amplify affective states. This study examined the relation between visual imagery (both trait usage and intrusive experiences of such imagery), intrusive verbal thought, and hypomania, as assessed by self-report questionnaires, in a sample of young adults (N=219). Regression analyses found (after controlling for anxiety, depression, and positive and negative affect) that levels of intrusive visual imagery predicted levels of hypomania, but that neither trait use of visual imagery nor intrusive verbal thought did. These results were consistent with the proposal that being a 'visualiser', as opposed to a 'verbaliser', is a risk factor for bipolar disorder, with the caveat that it is specifically intrusive experiences of imagery, rather than the tendency to utilize imagery per se, that acts as a risk factor.

The journey through cannabis use: a qualitative study of the experiences of young adults with psychosis.

The present study explored the personal experiences of cannabis and psychosis among young adults, including the reasons and meanings of cannabis use and the perceived relationship between cannabis and mental health. Interviews with seven young adults with psychosis who described regular current or past cannabis use were conducted and analyzed using Interpretative Phenomenological Analysis. Four master themes emerged: The Journey Through Cannabis Use, The Social and Cultural World, The Struggle to Make Sense, and The Depths and Beyond. Respondent validation supported these themes, particularly the idea of cannabis use as a journey that changed in time. Social and cultural factors clearly influenced the initiation of and decision whether to continue using cannabis. Individuals could simultaneously hold positive and negative views on using cannabis. Implications for clinical interventions are explored, and the relevance of motivational interviewing and the stages of change models of behavior change are noted.

Making sense of theory of mind and paranoia: the psychometric properties and reasoning requirements of a false belief sequencing task.

INTRODUCTION. This study used Item-Response Theory (IRT) to model the psychometric properties of a false belief picture sequencing task. Consistent with the mental time travel hypothesis of paranoia, we anticipated that performance on this deductive theory of mind (ToM) task would not be associated with the presence of persecutory delusions but would be related to other clinical, cognitive, and demographic factors. METHOD. A large (N=237) and diverse clinical and nonclinical sample differing in levels of depression and paranoid ideation performed 2 ToM tasks: the false belief sequencing task and a ToM stories task that was used to assess the validity of the false belief sequencing task as a measure of ToM. RESULTS. A unidimensional IRT model was found to fit the data well. Latent ToM ability as measured by the false belief sequencing task was negatively related with age and positively with IQ. In contrast to the ToM stories measure, there was no association between clinical diagnosis or symptoms and false belief picture sequencing after controlling for age and IQ. CONCLUSIONS. In line with mental time travel hypothesis of paranoia (Corcoran, 2010 ), performance on this deductive nonverbal ToM task is not related to the presence of paranoid symptoms. This measure is best suited for assessing ToM functioning where participants' performance falls just short of the average latent ToM ability. Furthermore, it is sensitive to the effects of increasing age and decreasing IQ.

Do specific types of sleep disturbances represent risk factors for poorer health-related quality of life in inflammatory bowel disease? A longitudinal cohort study.

OBJECTIVES: Poor global sleep quality is commonly reported in people with inflammatory bowel disease (IBD) and is linked to poorer health-related quality of life (HRQoL). However, understanding is currently limited by a lack of: (1) longitudinal research and (2) research investigating the impact of specific types of problems sleeping on IBD-related outcomes, particularly on HRQoL. DESIGN: Observational longitudinal cohort study. METHODS: N = 276 participants with IBD completed measures at baseline (T1) and 4 weeks later at T2. Four specific sleep disturbances associated with IBD including sleep apnoea, insomnia, restless legs, and nightmares were measured alongside depression, anxiety and stress, and HRQoL. RESULTS: After controlling for participant demographics and clinical characteristics, T1 depression, anxiety, stress, and T1 HRQoL, more severe symptom severity of sleep apnoea (B = -0.30, p < .05) and insomnia symptoms (B = -0.23, p < .05) at T1 significantly predicted poorer HRQoL at T2. However, the experience of restless legs (B = -0.03, p > .87) and nightmares (B = -0.14, p > .11) at T1 did not predict HRQoL. CONCLUSION: Symptoms synonymous with sleep apnoea and insomnia might represent modifiable risk factors that provide independent contributions to HRQoL over time in those with IBD. These findings suggest that interventions designed to improve sleep apnoea and insomnia could confer benefits to HRQoL in those with IBD. However, more longitudinal research is needed to understand the contribution of sleep disturbances over the longer term, as well as more randomized controlled trials testing the effect of improving sleep on IBD-related outcomes.

Predicting the development of psychological morbidity in inflammatory bowel disease: a systematic review.

BACKGROUND: Psychological morbidity in inflammatory bowel disease is common with significant impact on quality of life and health outcomes, but factors which predict the development of psychological morbidity are unclear. AIM: To undertake a systematic literature review of the predictors of psychological morbidity in patients with inflammatory bowel disease. METHODS: Electronic searches for English-language articles were performed with keywords relating to psychological morbidity according to the Diagnostic and Statistical Manual of Mental Disorders IV and subsequent criteria, and inflammatory bowel disease; in MEDLINE, PsychInfo, Web of Science and EMBASE for studies published from January 1997 to 25 January 2019. RESULTS: Of 660 studies identified, seven met the inclusion criteria. All measured depression, with three also measuring anxiety. Follow-up duration was variable (median of 18 months range 6-96 months). Risk factors identified for development of psychological morbidity included physical factors: aggressive disease (HR 5.77, 95% CI 1.89 to 17.7) and greater comorbidity burden (OR 4.31, 95% CI 2.83 to 6.57) and psychological risk factors: degree of gratitude (r=-0.43, p<0.01) and parenting stress (R-change=0.03, F(1,58)=35.6, p<0.05). Age-specific risk was identified with young people (13-17 years) at increased risk. CONCLUSIONS: Identifiable risks for the development of psychological morbidity in inflammatory bowel disease include physical and psychological factors. Further research is required from large prospective studies to enable early interventions in those at risk and reduce the impact of psychological morbidity.

Improving sleep quality leads to better mental health: A meta-analysis of randomised controlled trials.

The extent to which sleep is causally related to mental health is unclear. One way to test the causal link is to evaluate the extent to which interventions that improve sleep quality also improve mental health. We conducted a meta-analysis of randomised controlled trials that reported the effects of an intervention that improved sleep on composite mental health, as well as on seven specific mental health difficulties. 65 trials comprising 72 interventions and N = 8608 participants were included. Improving sleep led to a significant medium-sized effect on composite mental health (g+ = -0.53), depression (g+ = -0.63), anxiety (g+ = -0.51), and rumination (g+ = -0.49), as well as significant small-to-medium sized effects on stress (g+ = -0.42), and finally small significant effects on positive psychosis symptoms (g+ = -0.26). We also found a dose response relationship, in that greater improvements in sleep quality led to greater improvements in mental health. Our findings suggest that sleep is causally related to the experience of mental health difficulties. Future research might consider how interventions that improve sleep could be incorporated into mental health services, as well as the mechanisms of action that explain how sleep exerts an effect on mental health.

Consensus standards of healthcare for adults and children with inflammatory bowel disease in the UK.

OBJECTIVE: Symptoms and clinical course during inflammatory bowel disease (IBD) vary among individuals. Personalised care is therefore essential to effective management, delivered by a strong patient-centred multidisciplinary team, working within a well-designed service. This study aimed to fully rewrite the UK Standards for the healthcare of adults and children with IBD, and to develop an IBD Service Benchmarking Tool to support current and future personalised care models. DESIGN: Led by IBD UK, a national multidisciplinary alliance of patients and nominated representatives from all major stakeholders in IBD care, Standards requirements were defined by survey data collated from 689 patients and 151 healthcare professionals. Standards were drafted and refined over three rounds of modified electronic-Delphi. RESULTS: Consensus was achieved for 59 Standards covering seven clinical domains; (1) design and delivery of the multidisciplinary IBD service; (2) prediagnostic referral pathways, protocols and timeframes; (3) holistic care of the newly diagnosed patient; (4) flare management to support patient empowerment, self-management and access to specialists where required; (5) surgery including appropriate expertise, preoperative information, psychological support and postoperative care; (6) inpatient medical care delivery (7) and ongoing long-term care in the outpatient department and primary care setting including shared care. Using these patient-centred Standards and informed by the IBD Quality Improvement Project (IBDQIP), this paper presents a national benchmarking framework. CONCLUSIONS: The Standards and Benchmarking Tool provide a framework for healthcare providers and patients to rate the quality of their service. This will recognise excellent care, and promote quality improvement, audit and service development in IBD.

What is it like to receive a diagnosis of nonepileptic seizures?

The aim of this qualitative study was to provide insight into the experience of receiving the diagnosis of nonepileptic seizures (NES) from the patient's perspective. Semistructured interviews were conducted with eight patients who had received the diagnosis of NES over the preceding 6 months. All participants were on a waiting list for psychological treatment. Verbatim records of the interviews were analyzed using interpretative phenomenological analysis (IPA). Six main themes emerged from the data ("the experience of living with nonepileptic seizures", "label and understanding", "being left in limbo land", "doubt and certainty", "feeling like a human being again", and "emotional impact of diagnosis"). An ability to integrate the diagnosis into a personal narrative was key to participants' acceptance of the diagnosis. The communication of the diagnosis left some participants feeling distressed. The results suggest that patients need more time and resources to understand the diagnosis and more support after they have received it.

The Role of Experiential Avoidance and Parental Control in the Association Between Parent and Child Anxiety.

Parenting behavior and practices contribute to the intergenerational relationship between parent and child anxiety, with parental control being a consistent predictor of child anxiety. Parental experiential avoidance refers to how a parent copes with their internal world in the context of parenting. Little is known about how this relatively new parenting concept relates to child anxiety. The current study tested the indirect effect of parent anxiety on child anxiety through parental control and parental experiential avoidance; the indirect effect of parent anxiety on parental control through parental experiential avoidance; and the moderating effect of parental experiential avoidance on the relationship between parental control and child anxiety. Using a cross-sectional design, parents (N = 85) from a community sample of 8-12-year-old children self-reported on a survey measuring parent anxiety, child anxiety, parental control, and parental experiential avoidance. A hierarchical regression indicated that parental experiential avoidance significantly predicted child anxiety and accounted for further variance in child anxiety, over, and above parental control. There was an indirect effect of parent anxiety on child anxiety through parental control and parental experiential avoidance. Parental experiential avoidance moderated the relationship between parental control and child anxiety, such that the relationship was only significant at high levels of parental experiential avoidance. The current study provides support for the role of parental experiential avoidance in an intergenerational understanding of anxiety. Future research should replicate the study with a clinical sample. Theoretical and practice implications are considered.

A systematic review of the role of parents in the development of anxious cognitions in children.

Anxious cognitions and parental behavior are important in the development of child anxiety. The current review aims to appraise the literature on the relationship between parental factors and chid anxious cognitions. Online database searches of PsycInfo, Scopus, ProQuest Dissertations and Web of Science were systematically searched using key terms related to 'parent', 'child', 'anxiety' and 'cognitions'. Included studies (N = 13) were quality assessed and study findings were appraised in line with cognitive behavioral frameworks of the parental pathways to the development of anxious cognitions in children. Reviewed studies confirmed that parental factors have a role in the development of their children's anxious cognitions by modelling fearful responses, reducing their child's autonomy, and indirectly via their own expectations about their child. Limitations of the literature are considered, including issues of measurement. Future research should consider multi-modal assessment of parental factors and examine parental behavior and child anxious cognitions in the context of real-life threatening events.

Experimental effects of mindfulness inductions on self-regulation: Systematic review and meta-analysis.

Self-regulation is the control of aspects of the self to allow pursuit of long-term goals, and it is proposed as a central pathway through which mindfulness may exert benefits on well-being. However, the effects of a single mindfulness induction on self-regulation are not clear, as there has been no comprehensive review of this evidence. The current review synthesized existing findings relating to the effect of a mindfulness induction delivered in a laboratory setting on measures of self-regulation. Twenty-seven studies were included and grouped according to 3 outcomes: regulation of experimentally induced negative affect (k = 15; meta-analysis), emotion-regulation strategies (k = 7) and executive functions (k = 9; narrative synthesis). A mindfulness induction was superior to comparison groups in enhancing the regulation of negative affect (d = -.28). Executive-function performance was enhanced only when the experimental design included an affect induction or when the outcome was sustained attention. The effect on emotion-regulation strategies was inconclusive, but with emerging evidence for an effect on rumination. Overall, the findings indicate that, in the form of an induction, mindfulness may have the most immediate effect on attention mechanisms rather than exerting cognitive changes in other domains, as are often reported outcomes of longer mindfulness training. Through effecting change in attention, emotion regulation of negative affect can be enhanced, and subsequently, executive-function performance more quickly restored. The interpretations of the findings are caveated with consideration of the low quality of many of the included study designs determined by the quality appraisal tool. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

A systematic review of self-report measures of paranoia.

Paranoia can be conceptualized as consisting of a hierarchy of cognitions, ranging from commonly experienced thoughts about less severe perceived threats, up to less common, persecutory thoughts about extreme threats, which are associated with distressing psychosis. This review systematically appraises self-report paranoia questionnaires validated for use among the general population; the type of paranoia assessed, measurement or psychometric properties, and subsequent validation with clinical samples are all considered. A systematic literature search was performed using PubMed, Web of Science, and PsycINFO databases. Study methodologies and measurement properties were evaluated according to COnsenus-based Standards for the selection of health-based Measurement Instruments (Mokkink et al., 2012). Twenty-six studies, describing the validation of nine paranoia-related questionnaires, were identified. Questionnaires were reviewed in relation to the hierarchy of paranoia; with 2 questionnaires assessing "low-level" paranoia, 4 assessing persecutory thoughts, and the remainder assessing paranoia across this continua. Questionnaires assessing the full hierarchy of paranoid thoughts, alongside associated dimensions such as preoccupation, conviction, and distress, offer the most comprehensive assessment of paranoia in both nonclinical and clinical populations. Of the measures which do this, the Green et al. (2008) Paranoid Thoughts Scale had the strongest evidence for its measurement properties and is, therefore, recommended as the most reliable and valid self-report assessment of paranoia currently available. However, this review illustrated that generally paranoia questionnaires lack high quality evidence for their measurement properties. Implications of these findings for clinical practice and research are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).