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Psychometric characteristics of role-play assessments of social skill in schizophrenia.

There is an extensive literature documenting that people with schizophrenia have marked impairments in social role functioning and social skill. One of the most widely employed strategies for assessing social skill has been role-play tests: simulated social interactions that are videotaped for subsequent behavioral coding. There has been considerable discussion of the validity of the approach in the literature, but there has not been adequate consideration of other psychometric characteristics of role-play tests. This paper examines the psychometric characteristics of a representative role-play measure: the Maryland Assessment of Social Competence (MASC). Data from 5 large schizophrenia studies that included the MASC were examined: a study of victimization in women who abuse drugs, a study of health care among people with diabetes, a study of vocational outcomes, a study of social skill among drug abusers, and a clinical trial comparing two antipsychotic medications. Data were examined in terms of five questions: (1) Can role-play scenes be rated reliably? (2) How are role-play ratings distributed across populations? (3) How many and which behaviors should be rated? (4) How many role-play scenes are required? (5) Is role-play behavior temporally stable? Overall, the data suggest that the MASC, and by implication other similar role-play procedures, does have good psychometric properties. However, several things often taken for granted in the literature warrant careful consideration in the design of research using role-play. Implications of the results for design of research are discussed.

Adult↗

Psychometric properties of the Stirling Eating Disorder Scales with bulimia nervosa patients.

BACKGROUND: The Stirling Eating Disorder Scales (SEDS) are described as a well-validated measure of anorexic and bulimic cognitions and behaviors. However, there is little published research that demonstrates or tests the psychometric properties of the SEDS. The aim of this study was to assess the internal consistency of the SEDS with a clinical population at a specialist eating disorders service. METHOD: This study was a cross-sectional component of a larger study (evaluating cognitive behavioural group treatment for bulimia nervosa). At assessment at a specialist eating disorders service, the SEDS was administered to a clinical sample of women with a diagnosis of bulimia nervosa (N=40). Cronbach's alpha coefficients were used to determine the internal consistency of the scales. RESULTS: While the internal consistency of the overall SEDS was good, the existing SEDS subscales lacked internal consistency. Only one of the eight subscales (perceived external control) had an acceptable alpha (>.700). By removing up to three questionnaire items for each subscale that most impaired the alpha, only two further subscales were raised to an acceptable alpha. The sample's scores did not closely reflect the reported norms. DISCUSSION: More studies are needed to determine the clinical and psychometric validity of the SEDS. However, the present findings indicate that the preliminary psychometric findings do not generalize to other adult clinical populations. Therefore, caution should be used when interpreting the results of the SEDS when working with adults with eating disorders.

Adult↗

Psychometric properties of the MOS (Medical Outcomes Study) Sleep Scale in patients with neuropathic pain.

OBJECTIVE: This study assessed the psychometric properties of the MOS Sleep Scale in neuropathic pain (NeP). METHODS: Psychometric properties were tested in patients with neuropathic pain enrolled in a prospective study exploring the effectiveness of gabapentin for 3 months. Participants also completed scales for pain intensity, anxiety, depression, disability, and health-related quality of life. Feasibility, reliability, validity and sensitivity to change were measured in this study. RESULTS: Six-hundred-three patients [58.4+/-14.4 years (65.1% female), mean+/-SD] with pain for 1.2+/-3.3 years were included. The MOS Sleep Scale was acceptable (items with missing data <10% and floor and ceiling effects <50% per item and <15% per domain) and reliable (Cronbach's alpha between 0.64 and 0.87, and test-retest intraclass correlation coefficients between 0.79 and 0.91, p<0.001 for all cases). After adjusting for confounders, the MOS Sleep Scale was able to distinguish between sex, present pain intensity, level of disability and presence of anxiety or depression. Correlations with other scales were moderate; rho-coefficients between -0.21 and 0.57 (p<0.01, all cases). The scale was sensitive to change after treatment with gabapentin; after adjusting, responders (50% reduction in baseline pain) showed a decrease in sleep problems index of -25.6+/-14.3 points vs. -12.1+14.5 points in nonresponders (F=80.5, df=1/398, p<0.0001). Score reduction in summary index and subscales correlated significantly with pain intensity reduction (Pearson r-coefficients between 0.428 and 0.116, p<0.01, all cases). CONCLUSIONS: The MOS Sleep Scale showed good psychometric properties and was sensitive to changes in patients with NeP of broad aetiology.

Adult↗

A psychometric analysis of the Intolerance of Uncertainty Scale among four racial groups.

Recent psychometric analyses examining the cross-cultural validity of key anxiety measures have suggested that some, such as the Anxiety Sensitivity Index (ASI), may hold different psychometric characteristics among different racial or national groups. The Intolerance of Uncertainty Scale (IUS) is a self-report measure that, like the ASI, appears to assess a predispositional risk for developing some anxiety and mood disorders. Despite its validation in both a French and English version, the majority of the research conducted on the IUS has used predominantly Caucasian samples. Given this, the purpose of this research was to examine and compare the psychometric properties of the IUS among non-clinical participants of four racial groups: African American, Caucasian, Hispanic/Latino, and Southeast Asian. The data suggested generally strong, and highly similar, estimates of reliability and validity across the four racial groups. The factor structure of the IUS, however, was poorly interpretable among any of the groups. Implications for use of the IUS with different racial groups are discussed.

Adolescent↗

The children's Yale-Brown obsessive-compulsive scale: psychometric properties of child- and parent-report formats.

The children's Yale-Brown obsessive-compulsive scale (CY-BOCS) is a commonly used, psychometrically sound clinician-rated instrument of pediatric obsessive-compulsive disorder (OCD) severity. Given the relatively direct rating format and potential benefits of alternative versions that could be easily administered to patients and parents, we developed and examined the psychometric properties of child- and parent-report formats of the CY-BOCS severity items. A total of 53 children and adolescents (8-17 years old) with OCD and their parents was administered the CY-BOCS, children's Yale-Brown obsessive-compulsive scale-child report (CY-BOCS-CR), children's Yale-Brown obsessive-compulsive scale-parent report (CY-BOCS-PR), and other measures of obsessive-compulsive symptoms, internalizing, and externalizing symptoms. In general, reliability and convergent and divergent validity of the CY-BOCS-CR/PR were satisfactory. Psychometric properties for the CY-BOCS-CR in those children and adolescents with externalizing behavior problems were lower relative to those without externalizing problems. Exploratory factor analyses identified a two-factor structure in both measures comprised of disturbance and severity factors. This study provides preliminary support for the use of child- and parent-report versions of the CY-BOCS.

Adolescent↗

Clinimetrics vs. psychometrics: an unnecessary distinction.

The term "clinimetrics" was introduced by Feinstein to describe an approach to scale development that ostensibly is different from the more traditional "psychometrics." I argue that, for a number of reasons, it is time for this term to retire from the scene. I show that the clinimetric approach is neither new nor unique, but is rather a subset of psychometrics. Further, because the majority of new developments in scale construction (e.g., new variations of the intraclass correlation, item response theory, structural equation modeling, and cognitive theories) are reported in the psychometric literature, use of the term "clinimetric," especially among people not exposed to traditional test theory, cuts them off from a rich source of information.

Health Status↗

The Short-Form Headache Impact Test (HIT-6) was psychometrically equivalent in nine languages.

BACKGROUND AND OBJECTIVE: This study examined the psychometric properties and equivalence of the six-item Headache Impact Test (HIT-6) across 11 languages in 14 countries. METHODS: A multicenter, international cross-sectional study conducted in a primary care setting. Data obtained from 1,171 adults from 14 countries who consulted their primary care physician for headache completed the HIT-6 questionnaire and a headache survey were included in this analysis. Item-level statistics (e.g., range of response choices used by participants), item-scale statistics (e.g., item-total correlations), scale level statistics (e.g., internal consistency reliability), and tests of differential item functioning were conducted to examine the psychometric properties of all HIT-6 translations and their comparability across translations. RESULTS: Across languages, missing data were low, item-scale correlations were high, reliability was adequate, and item-level statistics were generally comparable. We found only minor differential item functioning, suggesting that the HIT-6 translations are equivalent to the U.S. English form. CONCLUSIONS: Psychometric analyses indicate that most HIT-6 translations (Canadian English, French, Greek, Hungarian, UK English, Hebrew, Portuguese, German, Spanish, and Dutch) are comparable to U.S. English. Improvements may be needed in the Finnish and Slovakian translations and the appropriateness of using the HIT-6 in South Africa should be explored further.

Cross-Sectional Studies↗

Psychometric properties of the Toronto Alexithymia Scale (TAS-20) for substance users.

OBJECTIVE: To determine the psychometric properties of the Toronto Alexithymia Scale (TAS-20), an established self-report measure of alexithymia, for a substance user sample participating in a clinical trial of outpatient cognitive-behavioral therapies (N=230). METHODS: Confirmatory and exploratory factor analyses were used to determine the number and nature of the factors underlying the TAS-20 in a sample of substance users. Structural equation modeling was used to determine the predictive validity of the TAS-20. RESULTS: A factor structure comparable, but not identical, with TAS-20 psychometric results with other populations was found; alpha coefficients were .88 for the feelings factor, .62 for the external thinking factor, and .87 for the total score. Although, on average, the substance users did not appear to have elevated alexithymia scores compared with the undergraduate students, alexithymia predicted less treatment engagement, i.e., fewer sessions attended and weaker helping alliance. Alexithymia also predicted alcohol use outcomes but not drug use outcomes. The relation between alexithymia and drinking outcome was conditional on whether the patient was using solely alcohol at baseline. CONCLUSION: The TAS-20 has reasonably good psychometric properties in this sample, which might be improved by dropping several marginal questionnaire items. Alexithymia appears to attenuate substance abuse treatment engagement. More clinical and research experience with this construct and specific instrument in substance user samples is needed.

Adult↗

The Bath Adolescent Pain Questionnaire (BAPQ): development and preliminary psychometric evaluation of an instrument to assess the impact of chronic pain on adolescents.

Chronic pain causes significant problems in the lives of many adolescents, considerably affecting their physical, psychological and social functioning. The assessment of the multidimensional impact of chronic pain is an essential clinical task. This study reports on the development and psychometric evaluation of the Bath Adolescent Pain Questionnaire (BAPQ); an assessment tool designed specifically for use with adolescents who experience chronic pain. A sample of 222 adolescents (11-18 years) experiencing chronic pain completed the 109-item draft inventory. Participants were recruited from two different UK clinics. All participants responded to items using a 5-point frequency scale. Psychometric evaluation of the data resulted in a reduced inventory length of 61 items. Internal consistency of all seven questionnaire subscales was established using Cronbach's alpha. Comparative validity was undertaken by comparison of all individual subscales with existing validated measures (SCAS, CDI-S, FDI, Brief FAM. PCS and CASAFS). The temporal reliability of each inventory subscale was established using a sub-sample of 30 adolescent participants over a 17-day period. Psychometric evaluation of the data suggests the inventory yields both a reliable and valid assessment of the impact of chronic pain on the lives of adolescents. The BAPQ may offer a comprehensive way to assess the widespread deleterious impact of adolescent chronic pain in both a research and clinical setting. Further investigation is needed on the predictive validity of the subscales. Additional data from samples of patients with diagnoses that are not musculoskeletal in origin would be of great assistance.

Adolescent↗

The psychometric quality and clinical usefulness of three pain assessment tools for elderly people with dementia.

In view of the need for valid, reliable, and clinically useful scales to assess pain in elderly people with dementia, this study evaluated the psychometric properties of translated versions of the PAINAD, PACSLAC, and DOLOPLUS-2 scales. In an observational study design, two raters simultaneously assessed the nursing home residents (n=128) for pain during influenza vaccination and care situations. The PACSLAC was valued as the most useful scale by nurses. Cronbach's alpha was high (>.80) for the total scale at T2 and T3 and adequate for the 'Facial expression' and 'Social/personality/mood' subscales. IC scores for the 'Activity/body movement' and 'Physiological indicators/eating/sleeping changes/vocal behaviors' subscales were low. It demonstrated good validity and reliability, although the scale should be further refined. This refinement should increase homogeneity. The PAINAD showed good psychometric qualities in terms of reliability, validity, and homogeneity (alpha ranged .69-.74 at T2 and T3) (except for the 'Breathing' item). The PAINAD scale had lower scores for clinical usefulness in this sample. The Dutch version of the DOLOPLUS-2 was considered more difficult to use but showed acceptable psychometric qualities in terms of the issues assessed, except for the 'psychosocial reactions' subscale. IC of the DOLOPLUS were adequate for the total scale (alpha ranged .74-.75) and almost all subscales (alpha ranged .58-.80). Findings of this study provide evidence of validity and reliability of the three pain assessment scales. Now that a pain scale is available, future studies also need to focus on its implementation in nursing practice.

Adult↗

Male Sexual Health Questionnaire (MSHQ): scale development and psychometric validation.

OBJECTIVES: To validate a new, self-administered questionnaire for assessing key domains of sexual function and satisfaction in aging men with urogenital health concerns. METHODS: The initial items were identified by patient interviews, review of current reports, and expert panel solicitation. The resulting 25-item questionnaire was subjected to psychometric evaluation and refinement using two discriminant validity studies in aging men with urogenital symptoms compared with age-matched controls. Psychometric tests of reliability, discriminant, and criterion validity were performed. RESULTS: Qualitative testing revealed adequate comprehension and content validity of the initial item set. Two domains of sexual function (ejaculation, erection) were identified in the first discriminant validity study, each of which showed a high degree of internal consistency (alpha = 0.81 and alpha = 0.90, respectively) and test-retest reliability (r = 0.86 and r = 0.87, respectively). Both sexual function domains discriminated well between men with and without urogenital manifestations of lower urinary tract symptoms (LUTS) and sexual dysfunction (P <0.001). An additional domain of sexual satisfaction was added in the second validation study, with similarly high internal consistency (alpha = 0.90) and test-retest reliability (r = 0.88). Tests of convergent and divergent validity, including correlations with standardized scales for depression (Center for Epidemiologic Studies-Depressed Mood Scale), sexual function (International Index of Erectile Function), and life satisfaction (Fugl-Meyer), confirmed the criterion validity of the new measure. CONCLUSIONS: The Male Sexual Health Questionnaire assesses sexual function and satisfaction in older men with urogenital symptoms of LUTS and sexual dysfunction. This new instrument has excellent psychometric properties and is well suited for use in clinical and research settings.

Age Factors↗

The Portuguese version of the Epilepsy Surgery Inventory (ESI-55): cross-cultural adaptation and evaluation of psychometric properties.

The purpose of this study was to develop a Portuguese version of the Epilepsy Surgery Inventory (ESI-55) and to assess its psychometric properties. Sixty patients with temporal lobe epilepsy related to unilateral mesial temporal sclerosis who underwent presurgical evaluation at the Universidade Federal de São Paulo (UNIFESP) formed the sample for this study. The psychometric properties of the ESI-55 included: reliability, validity, and responsiveness. Internal consistency was high in all domains (Cronbach's alpha ranging from 0.76 for Social Function to 0.88 for Physical Function) except Overall Quality of Life (alpha=0.45). Test-retest reliability after 1 week was good, with the intraclass correlation coefficient ranging from 0.79 (Energy/Fatigue) to 0.92 (Role Limitations due to Emotional Problems). Interrater reliability ranged from 0.84 (Cognitive Function) to 0.94 (Role Limitations due to Physical Problems). For construct validity, we verified a high correlation between the ESI-55 and Health Assessment Questionnaire-8 for the Physical Function domain (Pearson linear correlation=-0.84), and a moderate correlation for the Pain domain (P=-0.58), but for the other subscales no correlation was detected. Beck Depression Inventory and ESI-55 domains were highly statistically correlated (ANOVA: P<0.005), but there was no association of the Cognitive Function and Role Limitations due to Memory Problems subscales with neuropsychological evaluation (Pearson coefficient: P>0.05). With respect to demographic characteristics, a statistically significant correlation was observed for the variable educational level (Student t, P<0.005) and ESI-55 scores. There was a high correlation between seizure frequency and ESI-55 domains for clinical variables (ANOVA, P<0.005). Surgical treatment in this series improved health-related quality of life in the seizure-free group in three domains--Health Perception (1.24), Emotional Well-Being (1.32), and Energy/Fatigue (1.48)-as reflected by the standard response mean and the effect size of the sample. Our results support the psychometric properties of the Portuguese version of the ESI-55 as a measure of health-related quality of life.

Adult↗

[Psychometric validation of translation to Spanish of the gastrointestinal symptoms rating scale (GSRS) and quality of life in reflux and dyspepsia (QOLRAD) in patients with gastroesophageal reflux disease].

INTRODUCTION: Pyrosis symptoms and their impact on the quality of life related with health (QLRH) are frequently evaluated in clinical trials. When a questionnaire is translated into a language other than the original, it is necessary to have a linguistic validation, although this is not sufficient unless the psychometric characteristics have been verified. This study aims to document the psychometric characteristics of the translation to Spanish of the gastrointestinal symptoms rating scale (GSRS) and quality of life in reflux and dyspepsia (QOLRAD). MATERIAL AND METHOD: One hundred fifty eight patients with pyrosis symptoms (age: 51.0; SD: 16.3 years; men: 42.4%) completed the translation to Spanish of the GSRS, the pyrosis version of the QOLRAD, the Short-Form-36 (SF-36) and the hospital of anxiety and depression (HAD) scale. Seventy six patients were given an appointment for a second visit after one week, to fill out the GSRS and QOLRAD again. RESULTS: The reliability of the internal consistence of the GSRS was 0.59-0.83 and that of the QOLRAD: 0.87-0.95, and test-retest reliability of the GSRS was 0.44-0.63 and QOLRAD: 0.77-0.85. Score of the important domains of the GSRS "reflux", "abdominal pain" and "indigestion" and above all those of the QOLRAD correlated significantly. The domain "abdominal pain" of the GSRS had a strong correlation (negative) with the relevant domains of the SF-36. The QOLRAD domains significantly correlated with all the related domains of the SF-36. CONCLUSIONS: The psychometric characteristics of the translation to Spanish of the GSRS and QOLRAD were good, with satisfactory reliability and validity. However, the test-retest reliability of the "reflux" domain of the GSRS was not optimum.

Adult↗

Covert attention affects the psychometric function of contrast sensitivity.

We examined the effect of transient covert attention on the psychometric function for contrast sensitivity in an orientation discrimination task when the target was presented alone in the absence of distracters and visual masks. Transient covert attention decreased both the threshold (consistent with a contrast gain mechanism) and, less consistently, the slope of the psychometric function. We assessed performance at 8 equidistant locations (4.5 degrees eccentricity) and found that threshold and slope depended on target location-both were higher on the vertical than the horizontal meridian, particularly directly above fixation. All effects were robust across a range of spatial frequencies, and the visual field asymmetries increased with spatial frequency. Notwithstanding the dependence of the psychometric function on target location, attention improved performance to a similar extent across the visual field.Given that, in this study, we excluded all sources of external noise, and that we showed experimentally that spatial uncertainty cannot explain the present results, we conclude that the observed attentional benefit is consistent with signal enhancement.

Adult↗

Psychometric evaluation of the 12-item short-form health survey (SF-12) in osteoarthritis and rheumatoid arthritis clinical trials.

BACKGROUND: The psychometric properties of the 12-Item Short-Form Health Survey (SF-12), a subset of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), have been tested in the general population and certain disease states. OBJECTIVE: The purpose of this study was to evaluate the psychometric properties of the SF-12 as a generic measure of health-related quality of life (HRQoL) in osteoarthritis (OA) and rheumatoid arthritis (RA) patient populations in clinical trials. METHODS: Data were aggregated from 5 clinical trials evaluating the efficacy of non-steroidal anti-inflammatory drugs in OA (n = 651) and RA (n = 693) patients. Patient assessments in these trials were made using the SF-36 and commonly used clinical measures of OA and RA at baseline and after up to 6 weeks of treatment. For the items of the SF-36 contained in the SF-12, the item missing rate, computability of scores, floor and ceiling effects, factor structure, and item-component correlations were evaluated. Clinical variables and correlations of physical component summary (PCS-12) and mental component summary (MCS-12) scores of the SF-12 with the corresponding SF-36 component summary scores (PCS-36 and MCS-36) were also examined. Analyses were conducted separately for OA and RA patients. RESULTS: A low individual SF-12 item missing rate (0.29% to 2.30%) and a high percentage score computability (90.9%-94.3%) were observed at baseline. No floor or ceiling effects at baseline were observed. The scree plot confirmed the 2-factor structure of the SF-12 items. Items belonging to the physical component correlated more strongly with the PCS-12 than with the MCS-12; similarly, items belonging to the mental component correlated more strongly with the MCS-12 than with the PCS-12. The correlations between the PCS-12 and PCS-36 and between the MCS-12 and MCS-36 ranged from 0.92 to 0.96 (P < 0.001) at baseline and at week 2, 4, or 6. Significant correlations ranging from -0.09 to -0.58 (P < 0.05) were observed between the SF-12 scores and clinical variables. CONCLUSION: The SF-12 appears to be a psychometrically sound tool for the assessment of HRQoL in OA and RA patients.

Anti-Inflammatory Agents, Non-Steroidal↗

Assessing satisfaction with pain medication in primary care patients: development and psychometric validation of a new measure.

BACKGROUND: The measurement of patient satisfaction with pain medication (SPM) is a potentially useful aid for health care decision-making, but no validated measures for SPM are known. OBJECTIVE: This study aimed to develop an instrument to assess this patient-reported outcome in primary care and to evaluate whether it satisfactorily fulfilled the required psychometric properties (ie, reliability, validity, and sensitivity to change). METHODS: The measure's content was obtained from literature reviews, focus groups, and expert opinion. A preliminary version of 14 self-administered items was obtained and tested in a prospective study in patients receiving pain medication. Item-total statistics and factor analysis were performed to obtain the final version. The final version was psychometrically validated by assessing feasibility, internal consistency (Cronbach's alpha), convergent validity (multivariant methods), discriminant validity in patients presenting pain relief (receiver operating characteristic curves), test-retest reliability (using the intraclass correlation coefficient [ICC] in patients maintaining medication), and sensitivity to change (in patients changing medication). RESULTS: A total of 1119 patients were recruited (626 women [55.9%]; mean [SD] age, 47.6 [15.36] years; primarily suffering musculoskeletal injury [50.7%]). Four items were deleted from the preliminary version owing to low item-scale correlation and/or factor loadings. The final factor analysis confirmed a 4-factor solution, which explained 81.4% of the variance in questionnaire scores. Adverse events, speed/duration of effect, functional benefit, and overall satisfaction dimensions were identified. Cronbach's alpha and ICC for the 10-item final version were >0.80 for the summary score and all dimensions. Pain-related characteristics (intensity, frequency, and degree of pain relief), but not patient-related characteristics, were independently associated with the summary score. The area under the curve was 0.78 for the summary score. Effect sizes and standardized response mean were > or = 0.84 for the summary score and all dimensions. CONCLUSION: The SPM questionnaire appears to have good acceptability as well as satisfactory psychometric properties, based on these analyses.

Adult↗

The pre-morbid psychometric profile is stable over time in subjects at high familial risk for affective disorders.

BACKGROUND: The pre-morbid personality profile 'autonomic lability' (e.g. elevated neuroticism, frequent somatic complaints and increased interpersonal sensitivity) is suggested to be an antecedent of major depression. Recently, we reported that the psychometric profile of healthy first-degree relatives of patients with an affective disorder (so-called high-risk probands; HRPs) was characterized by the personality trait 'rigidity' in association with 'autonomic lability' and speculated that such a profile might be a potential candidate for a true vulnerability marker for affective disorders. Because one major prerequisite for any valid vulnerability marker is its stability over time, we re-examined our HRPs about four years after index assessment. METHODS: Sixteen HRPs from the initial sample (n=54) participated in the follow-up investigation which, on average, took place 47 months after index assessment. All these HRPs had remained mentally healthy during the follow-up period. RESULTS: The psychometric profile was remarkably stable over the four-year period when considering the total group of the 16 HRPs. On an individual level, similar findings were obtained. Allowing a fluctuation within a narrowly defined 'band width', a constancy of the self-ratings was found in 75% of the HRPs, within a broader 'band width' this was the case in 88% of the HRPs. LIMITATIONS: The power of the present observations appears to be somewhat limited due to the still small sample size of HRPs re-investigated and the fact that the control probands were not yet re-examined. CONCLUSIONS: The present follow-up findings in 16 probands at high risk for an affective disorder indicate a sufficient stability of the psychometric profile over time, so that this requirement for a true vulnerability marker is fulfilled.

Adult↗

Measuring seasonality: psychometric properties of the Seasonal Pattern Assessment Questionnaire and the Inventory for Seasonal Variation.

There is a general consensus that seasonal changes in mood, behavior and vegetative functions vary in magnitude across the general population. Studying the dimension of seasonality requires reliable and valid measures. This study examined and compared the psychometric properties of the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Inventory for Seasonal Variation (ISV) in 148 college students; 73 also completed a retest 2 months later. Results indicated good psychometric properties for both scales in terms of score distributions, test-retest reliability, internal consistency, factor structure and item-latent trait relationships using item response theory. Given the long history of its use and some small psychometric and simplicity advantages for the SPAQ, its continued use as a dimensional measure of seasonality is indicated.

Adolescent↗