A psychometric assessment of the Circadian Amplitude and Phase Scale

The Circadian Amplitude and Phase Scale (CAPS) is a new self-report tool that aims to assess amplitude and phase. The CAPS consists of three factors made up of 38 items. Amplitude is posited to be assessed via two of these factors: time awareness (TA) and/or strength of preference (SOP). The remaining factor, phase, is assessed via the existing Preferences Scale (PS). Given there is no published research using this measure, the authors undertook two studies to examine its psychometric properties and construct validity. In a sample of 351 North American students, the authors identified a three-factor 34-item model using principal components analysis. The components explained 39% of the variance, and scale reliability ranged from 0.73 (SOP) to 0.88 (PS). The correlations between the components were small, suggesting they are each assessing different constructs. Thus, it is unlikely TA and SOP may both be indicators of amplitude. The distributions for each scale were divided into two groups (≤ 25th and ≥ 75th percentiles), and these groups were used to assess construct validity using alertness ratings by time-of-day. The results from a multivariate general linear model indicated a significant difference (p?相似文献   

The Temporal Experience of Pleasure Scale (TEPS): exploration and confirmation of factor structure in a healthy Chinese sample

Background

The Temporal Experience of Pleasure Scale (TEPS) is a measure specifically designed to capture the anticipatory and consummatory facets of pleasure. However, few studies have examined the structure of the measure in non-Western samples. The current study aimed to evaluate the factor structure and psychometric properties of the TEPS in a Chinese sample.

Methods

We administered the Chinese version of the TEPS to 2275 healthy Chinese college students. They were randomly split into two sub-samples. The first sub-sample was used for exploratory factor analysis (EFA) to examine the structure of the TEPS in a Chinese sample. The second sub-sample was used as a validation sample for the identified structure from the EFA and confirmatory factor analysis (CFA) was adopted.

Results

Results of the EFA suggested a four-factor model (consummatory contextual, consummatory abstract, anticipatory contextual, and anticipatory abstract factors) instead of the original two-factor model (consummatory and anticipatory factors) ascertained from Western samples in the United States. The CFA results confirmed these results in the second sub-sample. Internal consistency and test-retest stability of the TEPS factors were good.

Conclusions

The TEPS has four factors among Chinese participants. Possible reasons for cultural difference and potential applications of the TEPS for cross-cultural comparison are discussed.     

Development of the Assessment of Belief Conflict in Relationship-14 (ABCR-14)

Purpose

Nurses and other healthcare workers frequently experience belief conflict, one of the most important, new stress-related problems in both academic and clinical fields.

Methods

In this study, using a sample of 1,683 nursing practitioners, we developed The Assessment of Belief Conflict in Relationship-14 (ABCR-14), a new scale that assesses belief conflict in the healthcare field. Standard psychometric procedures were used to develop and test the scale, including a qualitative framework concept and item-pool development, item reduction, and scale development. We analyzed the psychometric properties of ABCR-14 according to entropy, polyserial correlation coefficient, exploratory factor analysis, confirmatory factor analysis, average variance extracted, Cronbach’s alpha, Pearson product-moment correlation coefficient, and multidimensional item response theory (MIRT).

Results

The results of the analysis supported a three-factor model consisting of 14 items. The validity and reliability of ABCR-14 was suggested by evidence from high construct validity, structural validity, hypothesis testing, internal consistency reliability, and concurrent validity. The result of the MIRT offered strong support for good item response of item slope parameters and difficulty parameters. However, the ABCR-14 Likert scale might need to be explored from the MIRT point of view. Yet, as mentioned above, there is sufficient evidence to support that ABCR-14 has high validity and reliability.

Conclusion

The ABCR-14 demonstrates good psychometric properties for nursing belief conflict. Further studies are recommended to confirm its application in clinical practice.     

Validating the German version of the Quality of Relationship Inventory: confirming the three-factor structure and report of psychometric properties

Research on psychosocial influences such as relationship characteristics has received increased attention in the clinical as well as social-psychological field. Several studies demonstrated that the quality of relationships, in particular with respect to the perceived support within intimate relationships, profoundly affects individuals' mental and physical health. There is, however, a limited choice of valid and internationally known assessments of relationship quality in Germany. We report the validation of the German version of the Quality of Relationships Inventory (QRI). First, we evaluated its factor structure in a representative German sample of 1.494 participants by means of confirmatory factor analysis. Our findings support the previously proposed three-factor structure. Second, importance and satisfaction with different relationship domains (family/children and relationship/sexuality) were linked with the QRI scales, demonstrating high construct validity. Finally, we report sex and age differences regarding the perceived relationship support, conflict and depth in our German sample. In conclusion, the QRI is a reliable and valid measurement to assess social support in romantic relationships in the German population.     

The UK Functional Assessment Measure (UK FIM+FAM): Psychometric Evaluation in Patients Undergoing Specialist Rehabilitation following a Stroke from the National UK Clinical Dataset

The UK Functional Assessment Measure (UKFIM+FAM) is the principal outcome measure for the UK Rehabilitation Outcomes Collaborative (UKROC) national database for specialist rehabilitation. Previously validated in a mixed neurorehabilitation cohort, this study is the first to explore its psychometric properties in a stroke population, and compare left and right hemispheric strokes (LHS vs RHS). We analysed in-patient episode data from 62 specialist rehabilitation units collated through the UKROC database 2010–2013. Complete data were analysed for 1,539 stroke patients (LHS: 588, RHS: 566 with clear localisation). For factor analysis, admission and discharge data were pooled and randomised into two equivalent samples; the first for exploratory factor analysis (EFA) using principal components analysis, and the second for confirmatory factor analysis (CFA). Responsiveness for each subject (change from admission to discharge) was examined using paired t-tests and differences between LHS and RHS for the entire group were examined using non-paired t-tests. EFA showed a strong general factor accounting for >48% of the total variance. A three-factor solution comprising motor, communication and psychosocial subscales, accounting for >69% total variance, provided acceptable fit statistics on CFA (Root Mean Square Error of Approximation was 0.08 and Comparative Fit Index/ Tucker Lewis Index 0.922/0.907). All three subscales showed significant improvement between admission and discharge (p<0.001) with moderate effect sizes (>0.5). Total scores between LHS and RHS were not significantly different. However, LHS showed significantly higher motor scores (Mean 5.7, 95%CI 2.7, 8.6 p<0.001), while LHS had significantly lower cognitive scores, primarily in the communication domain (-6.8 95%CI -7.7, -5.8 p<0.001). To conclude, the UK FIM+FAM has a three-factor structure in stroke, similar to the general neurorehabilitation population. It is responsive to change during in-patient rehabilitation, and distinguishes between LHS and RHS. This tool extends stroke outcome measurement beyond physical disability to include cognitive, communication and psychosocial function.     

Structure of the Children's Revised Impact of Event Scale (CRIES) with Children and Adolescents Exposed to Debris Flood

Aim

PTSD symptoms were pervasive among children and adolescents after experiencing or exposure to traumatic events. Screening and diagnosis of PTSD symptoms is crucial in trauma-related research and practice. The 13-item Children''s Revised Impact of Event Scale (CRIES) has been demonstrated to be a valid and reliable tool to achieve this goal. This study was designed to examine the psychometric properties of the 13-item CRIES in a sample of Chinese debris flood victims.

Methods

A total of 268 participants (145 girls, 123 boys) aged 8–18 years were recruited from an integral part of a service oriented project, supported by the Institute of Psychology, Chinese Academy of Sciences following the debris flood. The participants were given the 13-item CRIES 3 months after the debris flood.

Results

The results of confirmatory factor analysis indicated that a two-factor structure (intrusion+arousal vs avoidance) emerged as the model best fit in total sample, boys and girls subsamples, respectively. The scale was also demonstrated to have good internal consistency (Cronbach''s alpha = 0.83).

Conclusion

The study confirmed the good psychometric properties of the CRIES and its'' applicability to Chinese children and adolescents. Moreover, these findings imply that the CRIES factor structure is stable across age, gender, and different types of trauma.     

Initial psychometric characterization for the Portuguese version of the Morningness-Eveningness-Stability-Scale improved (MESSi)

ABSTRACT

This work reports the initial psychometric characterization of the Morningness-Eveningness-Stability-Scale improved (MESSi) for Portuguese young-adults (N = 466). A confirmatory factor analysis confirmed a three-factor model (i.e. Morning Affect, Eveningness and Distinctness) in our data, as originally proposed. Furthermore, construct validity evidence in relation to external variables (i.e. morningness/eveningness and satisfaction with life), as well as adequate reliability (i.e. internal consistency and test-retest reliability), were found. Finally, sex-based invariance and between-sex differences were investigated for the three subscales, as were correlations with age. Results point to the suitability of the MESSi for multi-cultural research on relevant and multiple aspects of chronotype.     

Cross-Cultural Validation of the High Blood Pressure Health Literacy Scale in a Chinese Community

BackgroundConsidering the importance of health literacy (HL) for the maximum yield from the hypertension control programs, development of a reliable and valid instrument of hypertension-related HL is critical. This study aimed to translate and validate the High Blood Pressure-Health Literacy Scale (HBP-HLS) into Chinese (C-HBP-HLS) and evaluate its psychometric properties in Chinese context.MethodBetween June 2013 and January 2014, a cross-sectional study was conducted among recruited hypertensive patients belonging to the Han and Kazakh-Chinese communities in Urumqi, Xinjiang, China.ResultsA pilot sample (n = 242) was selected for the exploratory factor analysis of the translated and modified instrument. Another sample (n = 308) was recruited for the confirmatory factor analysis. C-HBP-HLS consisted of five dimensions (Print Health Literacy, Medication Label, Understanding Ability, Newest Vital Sign Test, and Avoiding Food Allergy) containing 15 items, accounting for 77.7% of the total variance. The 5-factor model demonstrated a good overall fit. The scale-level content validity index was 0.85. Cronbach’s alpha of the overall scale was 0.78 and test-retest reliability was 0.96. Education level had a strong positive correlation with the scores for items Q1, Q2, and Q3(r = 0.481, 0.492, 0.475, respectively). Health Literacy scores among Kazakh patients were significantly lower than Han (7.13±7.90 vs. 30.10±13.42, Z = -14.573, P<0.001).ConclusionC-HBP-HLS demonstrated suitable factor structure and robust psychometric properties for measuring health literacy level among hypertensive patients in China.     

Psychometric Properties of the Multidimensional Health Locus of Control Scale Form C in a Non-Western Culture

Form C of the Multidimensional Health Locus of Control Scales (MHLC-C) was designed to investigate health-related control beliefs of persons with an existing medical condition. The aim of the present study was to examine the psychometric properties of this instrument in a culture characterized by external control beliefs and learned helplessness—contrary to the societal context of original test development. Altogether, 374 Hungarian patients with cancer, irritable bowel syndrome, diabetes, and cardiovascular and musculoskeletal disorders were enrolled in the study. Besides the MHLC-C, instruments measuring general control beliefs, anxiety, depression, self-efficacy, and health behaviors were also administered to evaluate the validity of the scale. Both exploratory and confirmatory factor analytic techniques were used to investigate the factor structure of the scale. Our results showed that the Hungarian adaptation of the instrument had a slightly different structure than the one originally hypothesized: in the present sample, a three-factor structure emerged where the items of the Doctors and the Others subscales loaded onto a single common component. Internal reliability of all three subscales was adequate (alphas between .71 and .79). Data concerning the instrument''s validity were comparable with previous results from Western countries. These findings may suggest that health locus of control can be construed very similarly to Western countries even in a post-communist society—regardless of the potential differences in general control beliefs.     

Factor Structure of the Japanese Version of the Edinburgh Postnatal Depression Scale in the Postpartum Period

Background

The Edinburgh Postnatal Depression Scale (EPDS) is a widely used screening tool for postpartum depression (PPD). Although the reliability and validity of EPDS in Japanese has been confirmed and the prevalence of PPD is found to be about the same as Western countries, the factor structure of the Japanese version of EPDS has not been elucidated yet.

Methods

690 Japanese mothers completed all items of the EPDS at 1 month postpartum. We divided them randomly into two sample sets. The first sample set (n = 345) was used for exploratory factor analysis, and the second sample set was used (n = 345) for confirmatory factor analysis.

Results

The result of exploratory factor analysis indicated a three-factor model consisting of anxiety, depression and anhedonia. The results of confirmatory factor analysis suggested that the anxiety and anhedonia factors existed for EPDS in a sample of Japanese women at 1 month postpartum. The depression factor varies by the models of acceptable fit.

Conclusions

We examined EPDS scores. As a result, “anxiety” and “anhedonia” exist for EPDS among postpartum women in Japan as already reported in Western countries. Cross-cultural research is needed for future research.     

La transición hacia el retiro: adaptación en una muestra de prejubilados españoles de la escala Retirement Satisfaction Inventory

Objectives

This study provides psychometric data for the Spanish adaptation of the scale of Retirement Satisfaction Inventory (RSI). We explore the factor structure and psychometric properties a sample of Spanish early retirees. RSI measures the motivation to retirement, satisfaction with life in retirement and leisure activities.

Material and methods

The RSI scale (Floyd et al, 1992) was applied to a sample of 638 Spanish early-pensioners with a mean age of 61.28 (SD: 5.77) years and a mean age at early retirement of 53.89 years (SD: 2.71). An exploratory factorial analysis was performed using the SPSS statistics package, and a confirmatory factorial using the AMOS 6.0 module. The data collection process was carried out by means of the questionnaires by post method.

Results

The adaptation of the RSI to Spanish showed a three-scale structure:: the reasons for retirement, satisfaction with life in retirement, and leisure activities. These scales showed a structure with four, two and three main factors, respectively, which differ slightly from those reported in the original instrument.The confirmatory factorial analysis demonstrated the optimum fit of the model for the three scales.

Conclusions

The RSI adaptation to Spanish provides a tool that could asses the motivation towards retirement during the leaving work process, satisfaction with retirement life, and the leisure sources in the Spanish early retired population.     

Psychometric Validation Study of the Liebowitz Social Anxiety Scale - Self-Reported Version for Brazilian Portuguese

Social Anxiety Disorder (SAD) is prevalent and rarely diagnosed due to the difficulty in recognizing its symptoms as belonging to a disorder. Therefore, the evaluation/screening scales are of great importance for its detection, with the most used being the Liebowitz Social Anxiety Scale (LSAS). Thus, this study proposed to evaluate the psychometric properties of internal consistency and convergent validity, as well as the confirmatory factorial analysis and reliability of the self-reported version of the LSAS (LSAS-SR), translated into Brazilian Portuguese, in a sample of the general population (N = 413) and in a SAD clinical sample (N = 252). The convergent validity with specific scales for the evaluation of SAD and a general anxiety scale presented correlations ranging from 0.21 to 0.84. The confirmatory factorial analysis did not replicate the previously indicated findings of the literature, with the difficulty being in obtaining a consensus factorial structure common to the diverse cultures in which the instrument was studied. The LSAS-SR presented excellent internal consistency (α = 0.90–0.96) and test-retest reliability (Intraclass Correlation Coefficient = 0.81; Pearson’s = 0.82). The present findings support those of international studies that attest to the excellent psychometric properties of the LSAS-SR, endorsing its status as the gold standard.     

肺癌患者心理弹性的影响因素及与社会支持和生活质量的关系研究

摘要 目的：探讨肺癌患者心理弹性的影响因素,分析肺癌患者心理弹性与社会支持和生活质量的关系。方法：选取2018年6月至2019年12月期间我院收治的173例肺癌患者（肺癌组）和同期于我院进行体检的116例健康者（对照组）,分别采用心理弹性量表（CD-RISC）、社会支持评定量表（SSRS）、健康状况调查简表（SF-36）评估所有受试者心理弹性、社会支持、生活质量。收集患者临床资料,分析肺癌患者心理弹性的影响因素。相关性分析采用Pearson检验。结果：肺癌组CD-RISC、SSRS、SF-36评分均低于对照组（P＜0.05）。不同年龄、性别、教育程度、性格特征、SSRS评分、治疗阶段、复发情况、转移情况患者之间CD-RISC评分比较差异显著（P＜0.05）。多重线性回归分析结果显示性别、教育程度、性格特征、SSRS评分、治疗阶段、复发、转移均为肺癌患者心理弹性的影响因素（P＜0.05）。Pearson相关分析结果显示肺癌患者CD-RISC评分与SSRS、SF-36评分均呈正相关（r=0.567、0.617,P=0.047、0.346）。结论：肺癌患者心理弹性较正常人降低,性别、教育程度、性格特征、SSRS评分、治疗阶段、复发、转移是影响肺癌患者心理弹性的主要因素。肺癌患者心理弹性与社会支持、生活质量均有关。     

Psychometric Properties of the Lexington Attachment to Pets Scale: Mexican Version (LAPS-M)

The Lexington Attachment to Pets Scale (LAPS) is perhaps the most widely used instrument to assess human emotional attachments to pets and is suitable for both dog and cat owners. However, this instrument has not been translated into Spanish. Thus, the present study aimed to assess the psychometric properties of the Mexican version of the Lexington Attachment to Pets Scale (LAPS-M), which was translated into Spanish and adapted for dog owners. We analyzed the internal consistency and factor structure in a convenience sample of 152 people; 56.6% were women and 43.4% were men, with a mean age of 32.4 years (SD = 10.9 years), who had, on average, two dogs for a period of 3.8 years. The results indicate that the scale has excellent internal consistency in its complete version, with a Cronbach's alpha of 0.96, and also in its three subscales, with Cronbach's alpha coefficients ranging from 0.83 to 0.94. Factor analysis suggests a unifactorial structure is appropriate. However, the goodness-of-fit indicated by confirmatory factor analysis statistics would likely improve with a larger sample size. When we compared the central tendency measures of the LAPS-M according to the type of relationship with the dog, we found higher scores among people who considered dogs to be family members than among those who considered dogs to be pets. Furthermore, people who reported that the relationship with their dog was burdensome or stressful had lower scores. We conclude that the Mexican version of the LAPS is adequate and that further studies with larger sample sizes will contribute to the evidence regarding its psychometric properties     

鼻咽癌放疗患者心理弹性的影响因素及与自我感受负担的关系分析

摘要 目的：观察鼻咽癌放疗患者心理弹性的影响因素,并分析心理弹性与自我感受负担（SPB）的关系。方法：选取2019年3月~2020年8月期间我院收治的鼻咽癌患者100例,采用中文版心理弹性量表（CD-RISC）观察鼻咽癌放疗患者心理弹性,采用自我感受负担（SPB）量表观察患者SPB情况,分析患者心理弹性的影响因素及其与SPB的关系。结果：鼻咽癌放疗患者CD-RISC乐观、坚韧、自强各维度评分及总分均低于国内常模（P<0.05）,SPB量表总分为（38.10±2.74）分,处于中等负担水平。Pearson相关性分析结果显示,鼻咽癌放疗患者心理弹性和SPB呈负相关（P<0.05）。鼻咽癌放疗患者心理弹性与接受放疗宣教情况、临床分期、家庭月收入、教育程度、年龄有关（P<0.05）。本研究表明,教育程度、临床分期、年龄及家庭月收入是鼻咽癌放疗患者心理弹性的影响因素（P<0.05）。结论：鼻咽癌放疗患者的心理弹性较差,且其SPB与心理弹性有一定的联系。患者心理弹性的影响因素包括年龄、家庭月收入、临床分期、教育程度,临床可结合以上因素制定针对性方案以改善患者心理弹性。     

Psychometric properties of the Chinese version of the Perceived Stress Scale in policewomen

Background

The 10-item Perceived Stress Scale (PSS-10) is one of most widely used instruments to measure a global level of perceived stress in a range of clinical and research settings. This study was conducted to examine the psychometric properties of the Simplified Chinese version of the PSS-10 in policewomen.

Methodology

A total of 240 policewomen were recruited in this study. The Simplified Chinese versions of the PSS-10, the Beck Depression Inventory Revised (BDI-II), and the Beck Anxiety Inventory (BAI) were administered to all participants, and 36 of the participants were re-tested two weeks after the initial testing.

Principal Findings

The overall Cronbach''s alpha was 0.86, and the test–retest reliability coefficient was 0.68. Exploratory Factor Analysis (EFA) yielded 2 factors with eigenvalues of 4.76 and 1.48, accounting for 62.41% of variance. Factor 1 consisted of 6 items representing “negative feelings”; whereas Factor 2 consisted of 4 items representing “positive feelings”. The item loadings ranged from 0.72 to 0.83. The Confirmatory factor analysis (CFA) indicated a very good fit of this two-factor model to this sample. The PSS-10 significantly correlated with both BDI-II and BAI, indicating an acceptable concurrent validity.

Conclusions

The Simplified Chinese version of the PSS-10 demonstrated adequate psychometric properties for evaluating stress levels. The results support its use among the Chinese population.     

Measurement Invariance of the WHODAS 2.0 in a Population-Based Sample of Youth

The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) is a brief measure of global disability originally developed for adults, which has since been implemented among samples of children and youth. However, evidence of its validity for use among youth, particularly measurement invariance, is lacking. Investigations of measurement invariance assess the extent to which the psychometric properties of observed items in a measure are generalizable across samples. Satisfying the assumption of measurement invariance is critical for any inferences about between-group differences. The objective of this paper was to empirically assess the measurement invariance of the 12-item interview version of the WHODAS 2.0 measure in an epidemiological sample of youth (15 to 17 years) and adults (≥ 18 years) in Canada. Multiple-group confirmatory factor analysis using a categorical variable framework allowed for the sequential testing of increasingly restrictive models to evaluate measurement invariance of the WHODAS 2.0 between adults and youth. Findings provided evidence for full measurement invariance of the WHODAS 2.0 in youth aged 15 to 17 years. The final model fit the data well: χ²(159) = 769.04, p < .001; CFI = 0.950, TLI = 0.958, RMSEA (90% CI) = 0.055 [0.051, 0.059]. Results from this study build on previous work supporting the validity of the WHODAS 2.0. Findings indicate that the WHODAS 2.0 is valid for making substantive comparisons of disability among youth as young as 15 years of age.     

Development and Validation of the Self-Acceptance Scale for Persons with Early Blindness: The SAS-EB

Investigations of self-acceptance are critical to understanding the development and maintenance of psychological health. However, valid and reliable instruments for measuring self-acceptance in persons with early blindness have yet to be developed. The current research describes three studies designed to develop and validate the Self-acceptance Scale for Persons with Early Blindness (SAS-EB). In Study 1, we developed the initial item pool. Thirty-three items were generated, based on data from specialized literature and from 2 focus groups. Items were organized in a three-factor structure, theoretically predicted for SAS-EB - (1) body acceptance, (2) self-protection from social stigmas, and (3) feeling and believing in one''s capacities. In Study 2, information obtained from a panel of 9 experts and 22 persons with early blindness representing the target population was used to refine the initial item pool, generating a new pool of 27 items. In Study 3, 318 persons with early blindness (141 women and 177 men), between 18 and 60 years of age (M = 37.74 years, SD = 12.37) answered the new pool of 27 items. After the elimination of 9 items using confirmatory factor analysis, we confirmed the theoretical three-factor structure of the SAS-EB. Study 3 also provided support for the scale''s internal consistency and construct validity. Finally, the psychometric properties of the SAS-EB, its utility, and its limitations are discussed along with considerations for future research.     

The Chinese Morningness-Eveningness-Stability-Scale improved (MESSi): validity,reliability, and associations with sleep quality,personality, affect and life satisfaction

ABSTRACT

Individual differences in time of day preference have important correlates. Morningness is associated with greater well-being, while eveningness is associated with more maladaptive behaviors, psychological distress, and disorder. The availability of valid, reliable, questionnaire scales is central to this ongoing research. The recently developed Morningness–Eveningness-Stability-Scale improved (MESSi) utilizes items from previously established scales to assess the dimensions of Morning Affect (MA), Eveningness (EV), and amplitude of diurnal variation/distinctness (DI). The current study developed a Chinese version of the MESSi scale. A sample of 767 Chinese university students completed the translated MESSi, the reduced Morningness-Eveningness Questionnaire (rMEQ), and scales assessing sleep quality, positive and negative affect, the big five personality dimensions, and life satisfaction. An independent sample of 80 undergraduates completed the MESSi twice over a 14–19 day period. Exploratory and confirmatory factor analysis both supported the original three-factor structure of the MESSi, with the subscales of MA, EV, and DI. Internal consistency and test–retest reliability were acceptable/good, and expected correlations with other measures were found, including: MA correlated positively with the rMEQ, conscientiousness, positive affect, and life satisfaction; EV correlated negatively with rMEQ and conscientiousness; DI correlated positively with poor sleep quality, negative affect, and neuroticism. Overall, the results support the validity and reliability of the Chinese version of the MESSi.     

A psychometric evaluation and validation of the Preferences Scale

The Preferences Scale (PS) is a new measure of morningness and therefore requires intensive investigation to establish its measurement properties and validity. A confirmatory factor analysis (CFA) of Smith and colleagues (2002) posited model structure was not optimal in both a student (n = 731) and working sample (n = 218). However, significant differences (p < 0.01) were found for times to sleep and wake between morning and evening types. Principal components and reliability analyses were used to develop a 6-item model comprising 2 factors using a student sample (n = 368). Cronbach's alpha for the PS was 0.73 and the factors explained 61% of the variance. The revised model was replicated via CFA in a separate student sample (n = 363). A subsequent CFA confirmed the model structure in the working sample. Cronbach's alpha was 0.74 and the factors explained 64% of the variance. Significant differences (p < 0.01) in self-reported alertness ratings between morning and evening types were obtained by time-of-day. These results provide preliminary support for the PS. The predictive efficacy of the PS requires further validation against a number of health and work-related variables.