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Research study complexity refers to variables that contribute to the difficulty of a clinical trial or study. This includes variables such as intervention type, design, sample, and data management. High complexity often requires more resources, advanced planning, and specialized expertise to execute studies effectively. However, there are limited instruments that scale study complexity across research designs. The purpose of this study was to develop and establish initial psychometric properties of an instrument that scales research study complexity.
Methods:
Technical and grammatical principles were followed to produce clear, concise items using language familiar to researchers. Items underwent face, content, and cognitive validity testing through quantitative surveys and qualitative interviews. Content validity indices were calculated, and iterative scale revision was performed. The instrument underwent pilot testing using 2 exemplar protocols, asking participants (n = 31) to score 25 items (e.g., study arms, data collection procedures).
Results:
The instrument (Research Complexity Index) demonstrated face, content, and cognitive validity. Item mean and standard deviation ranged from 1.0 to 2.75 (Protocol 1) and 1.31 to 2.86 (Protocol 2). Corrected item-total correlations ranged from .030 to .618. Eight elements appear to be under correlated to other elements. Cronbach’s alpha was 0.586 (Protocol 1) and 0.764 (Protocol 2). Inter-rater reliability was fair (kappa = 0.338).
Conclusion:
Initial pilot testing demonstrates face, content, and cognitive validity, moderate internal consistency reliability and fair inter-rater reliability. Further refinement of the instrument may increase reliability thus providing a comprehensive method to assess study complexity and related resource quantification (e.g., staffing requirements).
A short yet reliable cognitive measure is needed that separates treatment and placebo for treatment trials for Alzheimer’s disease. Hence, we aimed to shorten the Alzheimer’s Disease Assessment Scale Cognitive Subscale (ADAS-Cog) and test its use as an efficacy measure.
Methods
Secondary data analysis of participant-level data from five pivotal clinical trials of donepezil compared with placebo for Alzheimer’s disease (N = 2,198). Across all five trials, cognition was appraised using the original 11-item ADAS-Cog. Statistical analysis consisted of sample characterization, item response theory (IRT) to identify an ADAS-Cog short version, and mixed models for repeated-measures analysis to examine the effect sizes of ADAS-Cog change on the original and short versions in the placebo versus donepezil groups.
Results
Based on IRT, a short ADAS-Cog was developed with seven items and two response options. The original and short ADAS-Cog correlated at baseline and at weeks 12 and 24 at 0.7. Effect sizes based on mixed modeling showed that the short and original ADAS-Cog separated placebo and donepezil comparably (ADAS-Cog original ES = 0.33, 95% CI = 0.29, 0.40, ADAS-Cog short ES = 0.25, 95% CI =0.23, 0.34).
Conclusions
IRT identified a short ADAS-cog version that separated donepezil and placebo, suggesting its clinical potential for assessment and treatment monitoring.
Modern psychometric methods make it possible to eliminate nonperforming items and reduce measurement error. Application of these methods to existing outcome measures can reduce variability in scores, and may increase treatment effect sizes in depression treatment trials.
Aims
We aim to determine whether using confirmatory factor analysis techniques can provide better estimates of the true effects of treatments, by conducting secondary analyses of individual patient data from randomised trials of antidepressant therapies.
Method
We will access individual patient data from antidepressant treatment trials through Clinicalstudydatarequest.com and Vivli.org, specifically targeting studies that used the Hamilton Rating Scale for Depression (HRSD) as the outcome measure. Exploratory and confirmatory factor analytic approaches will be used to determine pre-treatment (baseline) and post-treatment models of depression, in terms of the number of factors and weighted scores of each item. Differences in the derived factor scores between baseline and outcome measurements will yield an effect size for factor-informed depression change. The difference between the factor-informed effect size and each original trial effect size, calculated with total HRSD-17 scores, will be determined, and the differences modelled with meta-analytic approaches. Risk differences for proportions of patients who achieved remission will also be evaluated. Furthermore, measurement invariance methods will be used to assess potential gender differences.
Conclusions
Our approach will determine whether adopting advanced psychometric analyses can improve precision and better estimate effect sizes in antidepressant treatment trials. The proposed methods could have implications for future trials and other types of studies that use patient-reported outcome measures.
The Glasgow Composite Measure Pain Scale (CMPS) for dogs suffering acute pain, developed using psychometric methodology, measures pain to a level of precision suitable for clinical trials. However, for routine clinical use, where the emphasis is on speed, ease of use, and guidance for analgesia provision, a short form (CMPS-SF) was developed. The CMPS-SF comprises six behavioural categories with associated descriptive expressions (items): vocalisation (4), attention to wound (5), mobility (5), response to touch (6), demeanour (5) and posture/activity (5). Items are placed in increasing order of pain intensity and numbered accordingly. The observer chooses that item within each category which best describes the dog's behaviour and ranked scores are summed; the maximum pain score is 24, or 20 if mobility is impossible to assess. Veterinary surgeons in Glasgow, University College Dublin and North Carolina Veterinary Schools completed the CMPS-SF for 122 dogs undergoing post-operative care and thereafter were asked “Do you think this animal requires analgesia? Yes/No”. The population difference in median pain score, for dogs considered to require analgesia (seven) compared with those that did not (three), was highly statistically significant (P < 0.001). Consideration of a clinical decision-point for analgesia gave an intervention level of 6/24, and 5/20 when section B (mobility assessment) could not be carried out. Difficulties in recognising pain contribute to the sub-optimal use of analgesics in veterinary practice. The CMPS-SF provides a practical means of assessing acute post-operative pain and provides guidance with regard to analgesic requirement, so improving pain management and welfare. The CMPS-SF can be downloaded from the Glasgow Pain and Welfare website at http://www.gla.ac.uk/vet/painandwelfare.
Quality of life (QoL) is an abstract construct that has been formally recognised and widely used in human medicine. In recent years, QoL has received increasing attention in animal and veterinary sciences, and the measurement of QoL has been a focus of research in both the human and animal fields. Lord Kelvin said “When you cannot measure it, when you cannot express it in numbers — you have scarcely in your thoughts, advanced to a stage of science, whatever the matter may be” (Lord Kelvin 1893). So are we able to measure animal QoL? The psychometric measurement principles for abstract constructs such as human intelligence have been well rehearsed and researched. Application of traditional and newer psychometric approaches is becoming more widespread as a result of increasing human and animal welfare expectations which have brought a greater emphasis on the individual. In recent decades the field of human medicine has developed valid measures of experienced pain and QoL of individuals, including those who are not capable of self-report. More recently, researchers who are interested in the measurement of animal pain and QoL have begun to use similar methodologies. In this paper, we will consider these methodologies and the opportunities and difficulties they present.
Health-related quality of life (HRQL) was defined for farmed animals and identified as an appropriate focus of integrative welfare measurement for farmed pigs that embraces measurement of positive welfare. The instrument for HRQL measurement was developed specifically for use by farmers and stockpersons, the prime carers of pigs, to increase ownership of welfare improvement amongst those groups. Using a psychometric approach to instrument development, relevant observations were determined by consultation with experienced farmers and stockpersons. These observations included causal variables (cause changes in HRQL) and indicator variables (manifest changes in HRQL). The variables selected as items in the structured questionnaire instrument were those most commonly applied by farmers and stockpersons and also were assigned similar quality-of-life impact by a range of experts including pig veterinary specialists and welfare scientists. The prototype instrument comprises a questionnaire with 98 causal variable items (covering five domains of welfare according with the Five Freedoms) and 30 indicator variable items. It was pre-tested with farmers and stockpersons on commercial farm units and was found to have content (face) validity and high utility. This tool is a novel measure of HRQL in farmed pigs that encompasses the measurement of positive welfare and promotes a move from welfare assurance to welfare enhancement. Further validation of the instrument is described in a companion paper in this issue.
Behavioural screening tools may be used to identify at-risk children in resource-limited settings in sub-Saharan Africa. The ASEBA forms (Child Behaviour Checklist and Youth Self-Report) are frequently translated and adapted for use in sub-Saharan African populations, but little is known about their measurement properties in these contexts.
Methods:
We conducted a systematic review of all published journal articles that used the ASEBA forms with sub-Saharan African samples. We evaluated the reported psychometric properties, as well as the methodological quality of the psychometric evaluations, using COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) guidelines.
Results:
Fifty-eight studies reported measurement properties of the ASEBA forms. Most studies came from Southern (n = 29, 50%) or East African (n = 25, 43%) countries. Forty-nine studies (84%) used translated versions of the tool, but details regarding the translation process, if available, were often sparse. Most studies (n = 47, 81%) only reported internal consistency (using coefficient alpha) for one or more subscale. The methodological quality of the psychometric evaluations ranged from ‘very good’ to ‘inadequate’ across all measurement properties, except for internal consistency.
Conclusions:
There is limited good quality psychometric evidence available for the ASEBA forms in sub-Saharan Africa. We recommend (i) implementing a standardised procedure for conducting and reporting translation processes and (ii) conducting more comprehensive psychometric evaluations of the translated versions of the tools.
The International Personality Item Pool (IPIP) five-factor model inventories are widely used for personality research and have been translated into multiple languages. However, the extent of the psychometric assessment of translated scales is variable, often minimal. The lack of psychometric scrutiny is particularly problematic because translation is an inherently complex process. Here, we present a structural analysis of one Spanish translation of the 50-item IPIP five-factor inventory in a sample of Peruvian, non-university educated, working adults (n = 778). A global confirmatory factor analytic (CFA) model of the a priori five factors failed to fit. So too did single factor models for four of the five factors, the exception being Neuroticism. Fit was improved via use of an exploratory structural equation measurement model, but the resultant solution showed very poor theoretical coherence. So, we explored the data for systematic measurement artefacts and sought to model them to improve the psychometric properties of the scale. Specifically, the pattern of factor loadings suggested that the lack of coherence might be due to the effects of the valence of item wording (i.e., positively or negatively worded items). CFA models including five substantive factors and a series of method factors modelling shared covariance based on item wording, improved fit and coherence. This investigation suggests that unless method factors are explicitly modelled the tested Spanish translation may not be suitable for use in certain Spanish-speaking countries or samples composed of non-university educated participants. More broadly, the study has implications for many translated scales, especially when used without thorough psychometric evaluation.
To review the psychometric properties of the questionnaires commonly filled in by children and adolescents to measure circadian preference.
Methods
We examined the Morningness-Eveningness Questionnaire for Children and Adolescents (MEQ-CA), the Morningness-Eveningness Scale for Children (MESC) and the Composite Scale of Morningness (CSM). We critically analyzed the reliability, in term of internal consistency (through the Cronbach's alpha) and test-retest reliability (through the correlation coefficient), and the type of validation against external criteria (objective assessment of the sleep/wake cycle, body temperature, hormones and other questionnaires). Fifty studies that reported these data were included in the review: 7 studies used the MEQ-CA, 28 used the MESC and 15 used the CSM.
Results
The percentage of studies reporting at least acceptable levels of internal consistency was high and similar between the three questionnaires. Evidence for test-retest reliability was scant, since only 3 studies were available; it was at least acceptable for the MESC (two studies with a time interval of 1 month), not acceptable for the MEQ-CA (one study with a time interval of 6 months), while no information was available for the CSM. As regards the validation evidence, the MEQ-CA has been validated by the highest number of external criteria (actigraphy, oral body temperature and other questionnaires), followed by the CSM (cortisol sampling and other questionnaires). The MESC has been validated only against self-report measures.
Conclusions
The present state of the art would suggest the use of the MEQ-CA to assess circadian preference in children and adolescents.
The way that people internalize adverse experiences plays an important role in the development of psychopathology. The Pathogenic Belief Scale (PBS) is intended to operationalize a transtheoretical understanding of repetitive patterns of emotion-laden beliefs that develop in childhood and continue to influence people's current experience. Using a cross-sectional survey design, we recruited a large heterogeneous sample of 246 clinic outpatients and 732 adults in the community. Besides the PBS, measures of adverse parenting experiences and common psychopathology were administered. An exploratory factor analysis of the total sample of 978 participants was conducted followed by a convergent validity analysis for the 246 clinic outpatients. The three-factor solution included “cannot rely on others,” “undeserving,” and “interpersonal guilt,” and it showed good psychometric properties, including convergent validity with the measures of adverse parenting experiences and psychopathology. The 34-item PBS offers a promising self-report measure that could help delineate and understand the pathogenic beliefs that heterogeneous samples of patients may hold. Pathogenic beliefs may be relevant to the psychotherapy process, regardless of model or theoretical context.
Perfectionism is a transdiagnostic risk factor across psychopathology. The Clinical Perfectionism Questionnaire (CPQ) was developed to assess change in order to provide clinical utility, but currently the psychometric properties of the CPQ with adolescents is unknown.
Aims:
To assess the factor structure and construct validity of the CPQ in female adolescents.
Method:
The CPQ was administered to 267 females aged 14–19 years of age. Confirmatory factor analysis (CFA) was used to examine the validity of the two-factor model and a second-order factor model. Pearson correlations were used to evaluate the relationships between the CPQ and a wide range of measures of perfectionism, psychopathology and personality traits.
Results:
The study demonstrated internal consistency, construct validity and incremental validity of the CPQ in a sample of female adolescents. The CFA in the present study confirmed the two-factor model of the CPQ with Factor 1 relating to perfectionistic strivings and Factor 2 representing perfectionistic concerns. The second-order two factor model indicated no deterioration in fit.
Conclusions:
The two-factor model of the CPQ fits with the theoretical definition of clinical perfectionism where the over-dependence of self-worth on achievement and concern over mistakes are key elements. The CPQ is suitable for use with female adolescents in future research that seeks to better understand the role of perfectionism in the range of mental illnesses that impact youth.
Envy is depicted as motivating destructive desires and actions intended to spoil or destroy that which is envied.
Aim:
To develop a new valid and reliable measure of malicious envy (C-BRES), which included items representing the cognitive, emotional and behavioural responses empirically associated with this emotion.
Method:
A total of 203 adults completed the new 22-item cognitive and behavioural responses to envy scale (C-BRES). Exploratory factor analysis was carried out to test for reliability and internal consistency of the C-BRES. Evidence towards the concurrent construct validity (convergent and discriminant) of the C-BRES was assessed through correlations with the Dispositional envy scale and other measures of psychosocial outcomes empirically linked to envy.
Results:
Factor analysis for categorical data identified five dimensions of envy, namely: injustice, hostility, malicious action tendencies, malicious feelings and behavioural responses. The reliability indices of the five factors and the total scale were satisfactory (>0.85). Evidence towards the concurrent construct validity (convergent and discriminant) of the C-BRES is reported. In particular, envy was associated with higher levels of depression, psychoticism, neuroticism, anger and lower levels of self-esteem and quality of life.
Conclusion:
All findings support the psychometric adequacy of the C-BRES.
To better understand the maintenance of chronic fatigue syndrome (CFS), a valid and reliable measure of cognitive and behavioural responses to symptoms is required. Such a measure could also assess beliefs and coping behaviours in the context of fatigue in other somatic conditions.
Aims:
We aimed to establish the psychometric properties of both the Cognitive and Behavioural Responses Questionnaire (CBRQ) and its shortened version (CBRQ-S) in adolescents with CFS.
Method:
The full questionnaire was completed by a clinical cohort of adolescents (n = 121) presenting to specialist CFS units in the UK.
Results:
Both the CBRQ and CBRQ-S had good internal consistency. The CBRQ scores were strongly associated with depression, anxiety, school and social functioning, but weakly associated with fatigue and physical functioning, providing evidence of validity.
Conclusion:
Both the 40-item and the 18-item versions of the CBRQ were found to be reliable and valid in adolescents with CFS. To minimize unnecessary burden, the 18-item version is favoured. Using this assessment tool in future studies, including intervention studies, may help to better target interventions during clinical practice and improve outcomes.
Although pregnancy increases the vulnerability to anxiety, no specific assessment instruments are usually used to detect it. The objective of this study was to adapt the Pregnancy Related Anxiety Questionnaire (PRAQ) to Spanish population, as well as analyze its validity and reliability. A sample of 367 nulliparous pregnant women with a normal risk status filled in a socio-demographic and obstetric-gynaecological questionnaire, the PRAQ, the Edinburgh Postnatal Depression Scale (EPDS) and the State-Trait Anxiety Inventory (STAI). After performing a factorial analysis, a five-factor model that explains 53.1% of the variance was obtained. Estimates of internal consistency reliability were adequate (range = .78 to .93) for the five factors included in the final confirmatory factor analysis, and for the total scale (.97). Significant correlation among PRAQ, EPDS, and STAI was found (p < .001). The 85th percentile (score 234 or more) was used as a cut-off point to identify those women with high pregnancy-specific anxiety. In accordance with the results obtained, the PRAQ can be considered a useful screening tool to evaluate pregnancy-related anxiety among the Spanish population.
Objectives: The aim of this study was to assess the psychometric properties of a Swedish version of the Hayling test (HT-S) and its clinical utility in a group of patients with different frontotemporal dementia (FTD) syndromes. Early diagnosis of FTD is a challenge and requires a broad arsenal of assessment methods, neuropsychological tests not the least. The Hayling test assesses executive functions including initiation, efficiency and response inhibition. Methods: Seventy-six healthy controls were included as well as patients with the behavioral variant FTD (bvFTD; n = 17), semantic dementia (SD, n = 6), and progressive supranuclear palsy (n = 12). The Color Word Interference Test was administered to examine the construct validity. Results: Age showed a correlation with better performances in younger participants whereas the importance of sex and education were less evident. The split half reliability and internal consistency were equal to, or better, than reported for the original version. The interrater reliability was excellent. The construct validity was supported, nevertheless indicating partly different processes behind the performances of the two tests. The FTD group performed significantly worse than healthy controls on efficiency and response inhibition and there were also significant differences in performances between the syndromes despite small samples. Conclusions: The psychometric properties and clinical utility of the Swedish version are satisfactory for measuring efficiency and response inhibition with results indicating dissimilar profiles in the performances in the different syndromes. These results need to be corroborated in larger samples. (JINS, 2019, 25, 195–203)
Age of onset is considered central to understanding the course of schizophrenia, yet little is known regarding its association with quality of life in general, and specifically among males and females.
Aims:
To examine the association between the age of schizophrenia onset and quality of life, in general, and among males and females, using data from a national sample and competing statistical models.
Methods:
Participants with a diagnosis of schizophrenia (N = 1624) completed the Manchester Short Assessment of Quality of Life (MSA-QoL) and were rated on a parallel measure by their professional caregivers (N = 578). Multiple regression analysis models were computed for self-appraised quality of life, and mixed models with random intercepts were used for caregivers. Six competing models were tested for parsimony for each rating source. Three models without adjustment and three models adjusted for confounding variables. Sensitivity analyses were conducted for males and females separately.
Results:
Age of onset was statistically significantly (P <.05) negatively associated with self-appraised and caregiver-appraised quality of life on aggregate and among females. Among males, a significant (P <.01) quadratic effect of onset age on self-appraised quality of life demonstrated a negative association up to onset age of 36.67 years, after which the association was positive.
Conclusions
An earlier age of onset is associated with a better quality of life in schizophrenia which is tentatively explained by social decline. Specific trends in psychiatric symptom severity may account for this association among females while social advantages may account for the particular results found among males.
Background: Guilt is commonly associated with distress and psychopathology. However, there is a lack of validated measures that assess how people cope with this aversive emotional and cognitive experience. Aims: We therefore developed and validated a self-report measure that assesses how people manage their guilt: the Guilt Management Scale (GMS). Method: The GMS was administered to a non-clinical (n = 339) and clinical (n = 67) sample, alongside other validated measures of guilt severity, coping, thought control and psychological distress. Results from a principal component analysis (PCA) and assessments of test–retest reliability and internal consistency are presented. Results: The PCA yielded a six subscale solution (Self-Punishment, Reparation, People-Focused, Spirituality, Avoidance and Metacognition), accounting for 56.14% of variance. Test–retest reliability and internal consistency was found to be good–excellent for the majority of subscales. Across samples, Self-Punishment was related to higher levels of guilt and distress whilst Metacognition and Reparation were related to less guilt and distress in the non-clinical sample only. Conclusions: This paper provides preliminary evidence for the psychometric properties of the GMS in a non-clinical sample. With development and validation in clinical samples, the GMS could be used to inform psychological formulations of guilt and assess therapy outcomes.
Cognitive deficits are a well-established feature of bipolar disorders (BD), even during periods of euthymia, but risk factors associated with cognitive deficits in euthymic BD are still poorly understood. We aimed to validate classification criteria for the identification of clinically significant cognitive impairment, based on psychometric properties, to estimate the prevalence of neuropsychological deficits in euthymic BD, and identify risk factors for cognitive deficits using a multivariate approach.
Methods
We investigated neuropsychological performance in 476 euthymic patients with BD recruited via the French network of BD expert centres. We used a battery of tests, assessing five domains of cognition. Five criteria for the identification of neuropsychological impairment were tested based on their convergent and concurrent validity. Uni- and multivariate logistic regressions between cognitive impairment and several clinical and demographic variables were performed to identify risk factors for neuropsychological impairment in BD.
Results
One cut-off had satisfactory psychometric properties and yielded a prevalence of 12.4% for cognitive deficits in euthymic BD. Antipsychotics use were associated with the presence of a cognitive deficit.
Conclusions
This is the first study to validate a criterion for clinically significant cognitive impairment in BD. We report a lower prevalence of cognitive impairment than previous studies, which may have overestimated its prevalence. Patients with euthymic BD and cognitive impairment may benefit from cognitive remediation.
Background: Cognitive models of generalized anxiety disorder (GAD) suggest that maladaptive behaviours may contribute to the maintenance of the disorder; however, little research has concentrated on identifying and measuring these behaviours. To address this gap, the Worry Behaviors Inventory (WBI) was developed and has been evaluated within a classical test theory (CTT) approach. Aims: As CTT is limited in several important respects, this study examined the psychometric properties of the WBI using an Item Response Theory approach. Method: A large sample of adults commencing treatment for their symptoms of GAD (n = 537) completed the WBI in addition to measures of GAD and depression symptom severity. Results: Patients with a probable diagnosis of GAD typically engaged in four or five maladaptive behaviours most or all of the time in an attempt to prevent, control or avoid worrying about everyday concerns. The two-factor structure of the WBI was confirmed, and the WBI scales demonstrated good reliability across a broad range of the respective scales. Together with previous findings, our results suggested that hypervigilance and checking behaviours, as well as avoidance of saying or doing things that are worrisome, were the most relevant maladaptive behaviours associated with GAD, and discriminated well between adults with low, moderate and high degrees of the respective WBI scales. Conclusions: Our results support the importance of maladaptive behaviours to GAD and the utility of the WBI to index these behaviours. Ramifications for the classification, theoretical conceptualization and treatment of GAD are discussed.
Background: Recent research has supported the efficacy of schema therapy as a treatment for personality disorders. A group format has been developed (group schema therapy; GST), which has been suggested to improve both the clinical and cost-effectiveness of the treatment. Aims: Efficacy studies of GST need to assess treatment fidelity. The aims of the present study were to improve, describe and evaluate a fidelity measure for GST, the Group Schema Therapy Rating Scale – Revised (GSTRS-R). Method: Following a pilot study on an initial version of the scale (GSTRS), items were revised and guidelines were modified in order to improve the reliability of the scale. Students highly experienced with the scale rated recorded GST therapy sessions using the GSTRS-R in addition to a group cohesion measure, the Harvard Community Health Plan Group Cohesiveness Scale – II (GCS-II). The scores were used to assess internal consistency and inter-rater reliability. Discriminant validity was assessed by comparing the scores on the GSTRS-R with the GCS-II. Results: The GSTRS-R displayed substantial internal consistency and inter-rater reliability, and adequate discriminate validity, evidenced by a weak positive correlation with the GCS-II. Conclusions: Overall, the GSTRS-R is a reliable tool that may be useful for evaluating therapist fidelity to GST model, and assisting GST training and supervision. Initial validity was supported by a weak association with GCS-II, indicating that although associated with cohesiveness, the instrument also assesses factors specific to GST. Limitations are discussed.