Psychometric Evaluation of the Diary for Irritable Bowel Syndrome Symptoms-Constipation in a Prospective Observational Study

OBJECTIVES

To evaluate the psychometric properties of the Diary for Irritable Bowel Syndrome Symptoms-Constipation (DIBSS-C), which was developed to support primary and secondary endpoints in irritable bowel syndrome (IBS) with predominant constipation (IBS-C) clinical trials.

METHODS

Observational data were collected from 108 adults with IBS-C using a smartphone-type device for 17 days. DIBSS-C data regarding bowel movements (BMs) were collected for each event (along with the Bristol Stool Form Scale); abdominal symptoms were rated each evening. Global status items and the Gastrointestinal Symptom Rating Scale-IBS were completed on day 10 and day 17 and the IBS-Symptom Severity Scale on day 17. Item-level performance, internal consistency reliability, test-retest reliability, and construct validity were evaluated.

RESULTS

The Abdominal Symptoms Domain score demonstrated high internal consistency reliability (Cronbach's alpha week 1 = 0.98; week 2 = 0.96) and test-retest reliability (intraclass correlation coefficient [ICC] = 0.93). Test-retest reliability was stronger for abdominal symptoms (ICC = 0.91-0.94) than for the frequency-based BM-related outcomes (ICC = 0.54-0.66). Key construct validity hypotheses were supported by moderate to strong correlations with the corresponding Gastrointestinal Symptom Rating Scale-IBS, IBS-Symptom Severity Scale, and Bristol Stool Form Scale items. All known-groups comparisons were statistically significant for the abdominal symptom items and domain score; evidence for known-groups validity of BM-related outcomes was supportive when based on constipation severity.

CONCLUSIONS

The results of this study provided key psychometric evidence for the DIBSS-C, ultimately contributing to its qualification by the US Food and Drug Administration for use in IBS-C clinical trials.

Evaluating the clinical utility of the Atopic Dermatitis Control Tool: measurement properties and agreement between patients' responses and clinicians' impressions of atopic dermatitis control

Previous analyses have demonstrated the validity and reliability of the Atopic Dermatitis Control Tool (ADCT) in assessing patient-perceived control of atopic dermatitis (AD). We evaluated levels of agreement between patient and clinician assessments of AD control using the ADCT and clinician global assessment of control, respectively, providing further support to the measurement properties of the ADCT.

Cross-Sectional Quantitative Evaluation of a Novel Patient-Reported Outcome Measure in Familial Chylomicronemia Syndrome

Background

Familial chylomicronemia syndrome (FCS) is a rare metabolic disorder that impacts physical, emotional, social, and cognitive functioning. The FCS-Symptom and Impact Scale (FCS-SIS) patient-reported outcome (PRO) measure assesses common symptoms and impacts of FCS. This study was conducted to evaluate cross-sectional psychometric properties of the FCS-SIS and its scoring method.

Methods

This multisite, cross-sectional, observational study of individuals with FCS was conducted in the United States and Canada. Participants completed a survey composed of 7 PRO measures, including the FCS-SIS, and questions about clinical characteristics and demographics. The structure of the FCS-SIS was evaluated using inter-item and item-scale correlations and internal consistency reliability. Construct, known-groups, and criterion validity were evaluated by examining associations between FCS-SIS item and composite scores and other measures included within the survey.

Results

Most of the 33 participants were female (63.6%) and White (78.1%). On average, participants reported first noticing FCS symptoms at ~16 years, with abdominal pain the most frequently reported initial symptom (n=20). Participants reported 2.5 acute pancreatitis attacks on average over the past year. Average FCS-SIS symptom item scores ranged from 1.8 to 3.9 (on a 0-to-10 scale [none-to-worst-possible]) within the 24-hour recall period, with an average Symptom composite score of 2.7. The average impact item scores on the FCS-SIS ranged from 1.6 to 3.0 (on a 0-to-4 scale), with an average Impact composite score of 2.1. Inter-item correlations between the FCS-SIS Symptom items ranged from 0.32 to 0.78. Corrected item-total correlations were highly satisfactory for Impact items, ranging from 0.62 to 0.85. All a priori validity hypotheses were supported by observed correlations and score differences between known groups.

Conclusion

The results of this study support the structure, reliability, and validity of the FCS-SIS, laying the psychometric groundwork for longitudinal evaluation of its utility in assessing treatment benefit in FCS clinical studies.

The Prader-Willi Syndrome Anxiousness and Distress Behaviors Questionnaire: Development and Psychometric Validation

OBJECTIVES

To facilitate the development of new therapies for Prader-Willi syndrome (PWS), we sought to develop a reliable and valid assessment of anxiousness and distress, common characteristics that have a significant negative impact on individuals with PWS and their families.

METHODS

The PWS Anxiousness and Distress Behaviors Questionnaire (PADQ) was developed with extensive input from clinical experts, as well as caregivers of individuals with PWS, who participated in iterative sets of qualitative interviews. The psychometric properties of the PADQ were subsequently demonstrated in a cross-sectional evaluation using data from the Global PWS Registry provided by > 400 caregivers and confirmed using data from a phase 3 clinical trial of an oxytocin analogue (intranasal carbetocin, LV-101).

RESULTS

Qualitative interview participants consistently endorsed the content of the PADQ and were confident they could accurately respond to each item based on their observations of their child's behavior. Analysis of cross-sectional data supported the computation of a total PADQ score, as well as the reliability and validity of the measure. The results of analyses using longitudinal clinical trial data confirmed these properties and provided evidence for the responsiveness of the PADQ, further supporting its appropriateness for the evaluation of new treatments targeting anxiousness and distress in PWS.

CONCLUSIONS

The current body of evidence supports the conclusion that the PADQ measures observable behaviors that are meaningful to patients and their families and provides a valid and reliable method to assess beneficial treatment effects for some of the most challenging behaviors associated with PWS.

Confirmatory psychometric evaluations of the Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite-CT)

The Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite-CT) was developed to assess weight-related physical and psychosocial functioning in the context of clinical trials. Data from two pivotal trials of once-weekly subcutaneous semaglutide for the purpose of weight management (NCT03548935 and NCT03552757) were analysed to confirm the structure, reliability, validity, and responsiveness of the IWQOL-Lite-CT and evaluate the magnitude of meaningful within-patient change in patients with overweight or obesity, with and without type 2 diabetes. Factor analyses and inter-item correlations confirmed the IWQOL-Lite-CT structure and scoring algorithm. Each composite score (physical, physical function, psychosocial, and total) demonstrated excellent internal consistency (Cronbach's alphas ≥ 0.82) and test-retest reliability (intraclass correlation coefficients ≥ 0.85) in both trials. Patterns of cross-sectional and longitudinal construct validity correlations were generally consistent with hypotheses. Each of the IWQOL-Lite-CT composites was able to discriminate between known groups. Effect sizes and paired t tests comparing IWQOL-Lite-CT scores at baseline and Week 68 were statistically significant for all composites in both trials (P < 0.0001), providing strong support for the ability to detect change. Results of anchor-based analyses supported responder thresholds ranging from 13.5 to 16.6 across composite scores. The IWQOL-Lite-CT, a comprehensive assessment of weight-related functioning from the patient perspective, is appropriate for use in clinical trials evaluating the efficacy of new treatments for weight management.

Development of the impact of weight on daily activities questionnaire: A patient-reported outcome measure

While patient-reported outcome measures are available to evaluate health-related quality of life and functioning in obesity, existing measures do not evaluate the impact of excess weight and weight loss on the ability to perform regularly occurring daily activities. Three iterative sets of qualitative interviews were conducted in two countries (United States, n = 23; United Kingdom, n = 23) with individuals with body mass index ≥30 kg/m² to inform development of the Impact of Weight on Daily Activities Questionnaire (IWDAQ) for use in clinical trials to evaluate daily activity limitations associated with excess weight. Candidate concepts were selected based on the literature, expert opinion, and previously conducted qualitative research, after which the draft IWDAQ was developed and tested. Interviews included a brief concept elicitation phase, followed by cognitive debriefing during which the IWDAQ was refined based upon participants' feedback. The IWDAQ uses a novel, adaptive questionnaire design, such that clinical trial participants choose the three IWDAQ activities they would most like to improve with weight loss and rate the degree of limitation in each of these activities at baseline. By allowing individuals participating in trials to identify and monitor changes in the activities they most want to see improve with weight loss, the 19-item IWDAQ has the potential to detect the benefits of weight-loss treatment that individuals with obesity value most.

Validation of a new measure of quality of life in obesity trials: Impact of Weight on Quality of Life-Lite Clinical Trials Version

The Impact of Weight on Quality of Life-Lite (IWQOL-Lite) is widely used in evaluations of weight-loss interventions, including pharmaceutical trials. Because this measure was developed using input from individuals undergoing intensive residential treatment, the IWQOL-Lite may include concepts not relevant to clinical trial populations and may be missing concepts that are relevant to these populations. An alternative version, the IWQOL-Lite Clinical Trials Version (IWQOL-Lite-CT), was developed and validated according to the US Food and Drug Administration's (FDA's) guidance on patient-reported outcomes. Psychometric analyses were conducted to validate the IWQOL-Lite-CT using data from two randomized trials (NCT02453711 and NCT02906930) that included individuals with overweight/obesity, with and without type 2 diabetes. Additional measures included the SF-36, global items, weight and body mass index. The IWQOL-Lite-CT is a 20-item measure with two primary domains (Physical [seven items] and Psychosocial [13 items]). A five-item Physical Function composite and Total score were also supported. Cronbach's alpha and intraclass correlation coefficients exceeded 0.77 at each time point; patterns of construct validity correlations were consistent with hypotheses; and scores demonstrated treatment benefit. The IWQOL-Lite-CT is appropriate for assessing weight-related physical and psychosocial functioning in populations commonly targeted for obesity clinical trials. Qualification from the FDA is being sought for use of the IWQOL-Lite-CT in clinical trials to support product approval and labelling claims.

Development of the Impact of Juvenile Metachromatic Leukodystrophy on Physical Activities scale

Background

Metachromatic leukodystrophy (MLD) is a rare disease with three forms based on the age at onset of signs and symptoms. The objective of this study was to develop a caregiver-reported clinical outcome assessment that measures impairments in physical functioning related to activities of daily living in patients with juvenile MLD.

Methods

A targeted literature review and exploration of proprietary research, including a conceptual model, were conducted. Concept elicitation interviews were conducted to elicit additional concepts related to impairments in patients’ physical functioning with caregivers of five individuals with juvenile MLD. Based on the research review and concept elicitation interviews, the conceptual model was updated and the Impact of Juvenile Metachromatic Leukodystrophy on Physical Activities (IMPA) scale draft items were created. Cognitive debriefing interviews were conducted with six additional caregivers to finalize the conceptual model and to refine the IMPA scale.

Results

Initially, 17 potentially important concepts were identified and addressed in the draft IMPA scale. Following the cognitive debriefing interviews, 15 activities/items remained: brush teeth, comb/brush hair, bathe/shower, dress self, eat, drink, use pencil/crayon, sit upright, use toilet, get on/off toilet, walk, use stairs, get in/out of bed, get in/out of chair/wheelchair, and get in/out of vehicle. Items that did not uniquely contribute to the purpose of the instrument were removed.

Conclusion

The IMPA scale, developed according to regulatory standards, provides a means of detecting changes in activities of daily living in individuals with juvenile MLD and can hence be used in future studies to measure benefits of therapeutic interventions.

Development of the Diary for Irritable Bowel Syndrome Symptoms to Assess Treatment Benefit in Clinical Trials: Foundational Qualitative Research

BACKGROUND

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain and alterations in bowel habits. Three subtypes are defined on the basis of stool patterns: diarrhea-predominant IBS, constipation-predominant IBS, and alternating or mixed IBS.

OBJECTIVES

To develop patient-reported outcome measures for qualification by the Food and Drug Administration to support product approvals and labeling in IBS; the article focuses on the qualitative research that provided the foundation for the new measures.

METHODS

Forty-nine concept elicitation and 42 cognitive debriefing interviews were conducted with subjects meeting Rome III criteria; additional criteria were imposed to yield a sample representative of the target patient population.

RESULTS

Although incomplete bowel movements, abnormal stool frequency and consistency, and abdominal pain, discomfort, and bloating were reported most frequently across concept elicitation interviews, the relative importance of specific symptoms varied by subtype. Among their five symptoms most important to treat, diarrhea-predominant and alternating or mixed IBS subjects frequently identified urgency, loose/watery stools, abdominal pain, and cramping, whereas constipation-predominant IBS subjects commonly included infrequent and incomplete bowel movements, bloating, and abdominal pain. The cognitive debriefing interviews facilitated refinement of each item set, supported minor modifications following translatability assessment, and suggested improvements to the electronic interface. Furthermore, subjects reported that every item was relevant and no concepts of importance were missing.

CONCLUSIONS

Results support the content validity of the IBS patient-reported outcome measures. A pilot study was recently initiated to inform item reduction, develop scoring algorithms, and provide preliminary psychometric information. Comprehensive psychometric evaluation and responder definition development will follow.

Development of the 7-Item Binge-Eating Disorder Screener (BEDS-7)

OBJECTIVE

Develop a brief, patient-reported screening tool designed to identify individuals with probable binge-eating disorder (BED) for further evaluation or referral to specialists.

METHODS

Items were developed on the basis of the DSM-5 diagnostic criteria, existing tools, and input from 3 clinical experts (January 2014). Items were then refined in cognitive debriefing interviews with participants self-reporting BED characteristics (March 2014) and piloted in a multisite, cross-sectional, prospective, noninterventional study consisting of a semistructured diagnostic interview (to diagnose BED) and administration of the pilot Binge-Eating Disorder Screener (BEDS), Binge Eating Scale (BES), and RAND 36-Item Short-Form Health Survey (RAND-36) (June 2014-July 2014). The sensitivity and specificity of classification algorithms (formed from the pilot BEDS item-level responses) in predicting BED diagnosis were evaluated. The final algorithm was selected to minimize false negatives and false positives, while utilizing the fewest number of BEDS items.

RESULTS

Starting with the initial BEDS item pool (20 items), the 13-item pilot BEDS resulted from the cognitive debriefing interviews (n = 13). Of the 97 participants in the noninterventional study, 16 were diagnosed with BED (10/62 female, 16%; 6/35 male, 17%). Seven BEDS items (BEDS-7) yielded 100% sensitivity and 38.7% specificity. Participants correctly identified (true positives) had poorer BES scores and RAND-36 scores than participants identified as true negatives.

CONCLUSIONS

Implementation of the brief, patient-reported BEDS-7 in real-world clinical practice is expected to promote better understanding of BED characteristics and help physicians identify patients who may have BED.

Psychometric validation of patient-reported outcome measures assessing chronic constipation

BACKGROUND

Measures assessing treatment outcomes in previous CC clinical trials have not met the requirements described in the US Food and Drug Administration's guidance on patient-reported outcomes.

AIM

Psychometric analyses using data from one Phase IIb study and two Phase III trials of linaclotide for the treatment of chronic constipation (CC) were conducted to document the measurement properties of patient-reported CC Symptom Severity Measures.

STUDY METHODS

Each study had a multicenter, randomized, double-blind, placebo-controlled, parallel-group design, comparing placebo to four doses of oral linaclotide taken once daily for 4 weeks in the Phase IIb dose-ranging study (n=307) and to two doses of linaclotide taken once daily for 12 weeks in the Phase III trials (n=1,272). The CC Symptom Severity Measures addressing bowel function (Bowel Movement Frequency, Stool Consistency, Straining) and abdominal symptoms (Bloating, Abdominal Discomfort, Abdominal Pain) were administered daily using interactive voice-response system technology. Intraclass correlations, Pearson correlations, factor analyses, F-tests, and effect sizes were computed.

RESULTS

The CC Symptom Severity Measures demonstrated satisfactory test-retest reliability and construct validity. Factor analyses indicated one factor for abdominal symptoms and another for bowel symptoms. Known-groups F-tests substantiated the discriminating ability of the CC Symptom Severity Measures. Responsiveness statistics were moderate to strong, indicating that these measures are capable of detecting change.

CONCLUSION

In large studies of CC patients, linaclotide significantly improved abdominal and bowel symptoms. These psychometric analyses support the reliability, validity, discriminating ability, and responsiveness of the CC Symptom Severity Measures for evaluating treatment outcomes in the linaclotide clinical studies.

Psychometric validation of symptom severity measures in irritable bowel syndrome with constipation

BACKGROUND

Historically, measures of symptom severity of irritable bowel syndrome with constipation (IBS-C) in clinical trials have not met the evidence requirements described in the FDA guidance on patient-reported outcomes (PROs), which describes the evidentiary requirements and review criteria for patient-reported outcome measures intended to support product approval or labelling claims.

AIM

Data from two phase 3 trials (N = 1608) of linaclotide for the treatment of IBS-C were analysed to evaluate the psychometric properties of patient-reported outcome measures assessing changes in the severity of abdominal and bowel symptoms.

METHODS

A set of patient-reported outcome assessments addressing abdominal and bowel symptoms, the IBS-C Symptom Severity Measures, were administered daily using interactive voice response system technology. Intraclass correlation coefficients (ICCs), Pearson correlations, factor analyses, F-tests and effect sizes were computed to evaluate the reliability, construct validity, discriminating ability and responsiveness of the IBS-C Symptom Severity Measures in a clinical trial context.

RESULTS

The IBS-C Symptom Severity Measures showed highly satisfactory test-retest reliability (ICCs ranging from 0.79 to 0.95) and construct validity. Factor analyses indicated one factor for abdominal symptoms and another for bowel symptoms. Known-groups F-tests comparing subgroups based on various responder definitions were statistically significant and in the expected direction, substantiating the discriminating ability of the IBS-C Symptom Severity Measures. Responsiveness statistics (ranging from 0.6 to 2.1) demonstrated these measures are also capable of detecting change.

CONCLUSIONS

The psychometric analysis results strongly support the reliability, construct validity, discriminating ability and responsiveness of the IBS-C Symptom Severity Measures and substantiate the conclusion of linaclotide treatment benefit.

Assessment of treatment response in chronic constipation clinical trials

Background

While chronic constipation (CC) clinical trials have focused primarily on bowel symptoms (symptoms directly related to bowel movements), abdominal symptoms are also prevalent among patients. The United States Food and Drug Administration’s (FDA’s) guidance on the use of patient-reported outcome measures to support product approvals or labeling claims recommends that endpoints be developed with direct patient input and include all symptoms important to patients.

Aim

To identify a comprehensive set of CC symptoms that are important to patients for measurement in clinical trials.

Methods

Following a targeted literature review to identify CC symptoms previously reported by patients, 28 patient interviews were conducted consistent with the FDA’s guidance on patient-reported outcomes. Subsequent to open-ended questions eliciting descriptions of all symptoms, rating and ranking methods were used to identify those of greatest importance to patients.

Results

All 67 studies reviewed included bowel symptoms; more than half also addressed at least one abdominal symptom. Interview participants reported 62 potentially distinct concepts: 12 bowel symptoms; 21 abdominal symptoms; and 29 additional symptoms/impacts. Patients’ descriptions revealed that many symptom terms were highly related and/or could be considered secondary to CC. The rating and ranking task results suggest that both bowel (for example, stool frequency and consistency) and abdominal symptoms (for example, bloating, abdominal pain) comprise patients’ most important symptoms. Further, improvements in both bowel and abdominal symptoms would constitute an improvement in patients’ CC overall.

Conclusion

Abdominal symptoms in CC patients are equal in relevance to bowel symptoms and should also be addressed in clinical trials to fully evaluate treatment benefit.

Quantitative challenges facing patient-centered outcomes research

Patient-centered outcomes research collects and analyzes data from patients and other stakeholders to improve health care delivery and outcomes and guide health care decisions. However, there are a number of challenges in conducting quantitative analyses of patient-centered data. This article provides an overview of the analytical challenges and describes approaches to consider to overcome the challenges, as well as directions for future development.

The development of a survey to measure completeness of response to migraine therapy

OBJECTIVE

To assess the psychometric properties of a new patient-reported migraine instrument, the Completeness of Response Survey (CORS), which measures a comprehensive set of factors important to patients' decisions regarding the initiation and continuation of treatment.

BACKGROUND

Traditionally, migraine treatments and the instruments used to demonstrate their efficacy have focused on the relief of headache pain. As new treatments emerge with the potential for more complete and consistent migraine relief, more comprehensive tools are needed to demonstrate these benefits. The CORS includes 2 modules, the static CORS, which comprehensively evaluates one treatment at one time point, and the comparative CORS, which provides a more global comparison between 2 treatments at one time point. Together, the 2 modules can measure unmet treatment needs and improvements over the course of a clinical study.

METHODS

Data from an 8-site study comparing 147 patients' recent experiences with their current triptan therapy and 2 months of study treatment with a single-tablet formulation of sumatriptan/naproxen sodium were used to conduct a preliminary psychometric evaluation of the CORS. The study included both modules of the CORS, the Headache Impact Test, the revised Patient Perception of Migraine Questionnaire, and a migraine diary.

RESULTS

The CORS response categories in both the static and comparative modules demonstrated limited floor or ceiling effects and few missing values (<3%). Inter-item correlations, principal components analysis (component loading range: 0.62 to 0.95), and high estimates of internal consistency (alpha range: 0.88 to 0.94) for each composite score supported the structure and proposed scoring algorithm for the static module. The pattern of correlations between the CORS static and comparative items and composites with the revised Patient Perception of Migraine Questionnaire items and subscales, as well as the relationships between responses to selected static CORS items and the migraine diary, supported the construct validity of the CORS.

CONCLUSIONS

The CORS is capable of demonstrating advantages of more comprehensive migraine therapies over traditional therapies, which are primarily focused on the resolution of headache pain, by addressing the frequency and speed with which the most common migraine symptoms are resolved and patients' return to normal functioning. This research shows evidence for the value and utility for the CORS static and comparative items and components, and further evaluation is underway.

Successful implementation of cognitive interviews in special populations

The cognitive interview, with a focus on debriefing methods, was developed in the 1980s to identify sources of potential response error in surveys or questionnaires. With the release of the final US FDA guidance, titled 'Patient-Reported Outcome Measures: Use in Medical Product Development to Support Labeling Claims', cognitive interviews have gained importance and relevance both for concept elicitation and debriefing purposes in the context of instrument development. This article is intended as a guide for the researcher working with special populations in methods to foster successful cognitive interviews that meet FDA standards. While many of these techniques are broadly applicable, specific recommendations are provided for working with pediatric and cognitively challenged populations, as well as with individuals with communication difficulties.

Development of a family functioning scale for major depressive disorder

OBJECTIVE

To better understand depression's impact on family functioning from the perspectives of patients with major depressive disorder (MDD) and their partners; to develop and test patient and partner versions of a new self-reported measure, the Depression and Family Functioning Scale (DFFS), for use in clinical trials.

METHODS

Concept elicitation interviews were conducted with 32 adults with clinician-diagnosed moderate-to-severe MDD and their respective partners. Twenty-six items were drafted to address relevant aspects of family functioning and were then tested and refined through two iterative sets of cognitive debriefing interviews, each conducted by the same pair of highly experienced researchers, including a licensed clinical psychologist.

RESULTS

Depression negatively affects family functioning through poorer communication, increased conflicts, decreased family interaction, and decreased intimacy. No existing instrument measured all domains of interest, or had been rigorously developed and psychometrically validated in the target populations. The draft DFFS items generally tested well and only minor modifications were made to the items after the second set of interviews. Both patients and partners indicated that the final set of 15 DFFS items addresses all concepts of importance.

CONCLUSIONS

The DFFS evaluates the impact of depression on family functioning and has the potential to provide important information that can facilitate a more comprehensive evaluation of new treatments in clinical trial settings. Although MDD severity was not confirmed with a standardized interview, in clinical practice in the US, MDD is generally not diagnosed with the use of a structured clinical interview or clinician-administered tool. In the current study, depression severity had little (if any) impact on the specific concepts elicited as being important to family functioning. In fact, patients with milder depression had more insight and were able to better articulate changes in family functioning with treatment.

Development of an electronic daily uterine fibroid symptom diary

BACKGROUND

In some women, uterine fibroids are associated with severe, disabling symptoms. There is a lack of high-quality evidence supporting the effectiveness of most interventions for symptomatic uterine fibroids. In part, this is due to the lack of available disease-specific instruments with comprehensive validation evidence that measure treatment benefit from the patient perspective.

OBJECTIVE

The aim of this study was to develop an electronic patient-reported outcomes (PRO) instrument that measures treatment benefit from the patient's perspective that is easily administered and practical for use in clinical trials. Rigorous methods that are consistent with the US FDA's PRO Guidance to Industry were employed.

METHODS

The study took place in two phases: a content development phase (eight focus groups; three sets of cognitive interviews) and a prospective non-intervention usability pilot phase. Both phases were conducted in the US. The study population comprised women diagnosed with symptomatic uterine fibroids. A total of 68 women (mean age 40 years) participated in the eight focus groups; 27 women (mean age 41 years) who were not part of the focus groups participated in the cognitive interviews. Fourteen additional women (mean age 39 years) participated in a usability pilot. Efforts were made to recruit a diverse population with respect to race and education.

RESULTS

After completing eight focus groups, no new symptom concepts or severity-level measurement ideas were introduced, indicating that concept saturation was achieved. Fourteen draft items were developed during the focus groups for testing in the cognitive interviews. Every symptom represented by the draft items was endorsed by at least two-thirds of the participants in the cognitive interviews. After completing three rounds of cognitive interviews, the Fibroid Symptom Diary© (FSD) contained eight items that assessed bleeding severity, menstrual cramping, and fibroid-related fatigue. An open-field item, tailored to each participant, was also included to assess the most bothersome fibroid-related pain. However, to accommodate electronic administration of the diary this item was replaced, prior to the usability pilot, with three pain-specific items (i.e. abdominal pain, low back pain, and pain during intercourse) that were most commonly expressed during the development phase. The final FSD includes 11 items: five addressing menstrual bleeding or spotting; one each relating to cramping (distinct from other pain), fatigue, and bloating; and three that address other fibroid-related pain. The average time for completing the diary was 1-2 minutes per day. A total of 118 daily diary records were collected from 14 participants (average of nine daily diary completions per participant; range 5-18 days) in the usability pilot. Seven participants completed the diary every day. Most participants experienced the majority of the symptoms included in the FSD.

CONCLUSIONS

The FSD captures the concepts most important to women with uterine fibroids and has strong evidence of content validity as required by the FDA PRO Guidance to Industry. Once fully validated, the FSD may replace other measures for assessing changes in symptoms and treatment benefit that are both burdensome to patients and cumbersome to trial sponsors.

Interpreting patient-reported outcome results: US FDA guidance and emerging methods

In recent years, the US FDA has become more critical of instruments used to measure patient-reported outcomes (PROs) in clinical trials. To facilitate decisions related to the approval of drugs, labels and promotional claims based on PROs, the FDA created the Study Endpoints and Label Development (SEALD) group. SEALD has developed a PRO guidance related to the use of PRO measures used to support drug approvals and label claims, including recommendations for establishing thresholds for meaningful change at the individual level (i.e., defining a responder). This article examines in detail the FDA-recommended methodology for defining a responder and analyzing responder-based PRO measure results. We also present other responder analysis approaches for consideration in furthering the precision and interpretation of this methodology.

Interpreting patient-reported outcome results: US FDA guidance and emerging methods

In recent years, the US FDA has become more critical of instruments used to measure patient-reported outcomes (PROs) in clinical trials. To facilitate decisions related to the approval of drugs, labels and promotional claims based on PROs, the FDA created the Study Endpoints and Label Development (SEALD) group. SEALD has developed a PRO guidance related to the use of PRO measures used to support drug approvals and label claims, including recommendations for establishing thresholds for meaningful change at the individual level (i.e., defining a responder). This article examines in detail the FDA-recommended methodology for defining a responder and analyzing responder-based PRO measure results. We also present other responder analysis approaches for consideration in furthering the precision and interpretation of this methodology.

Urgency as an Endpoint in Irritable Bowel Syndrome

BACKGROUND

The choice of endpoints is crucial for proper evaluation of agents in clinical trials of irritable bowel syndrome (IBS). In a recently published draft guidance for IBS from the United States Food and Drug Administration (FDA), urgency was not considered an appropriate primary endpoint. The FDA's position is that it is not clear how patients with diarrhea-predominant IBS (D-IBS) "define or describe urgency". The aims of this study were to evaluate the association of urgency with stool frequency and consistency in patients with D-IBS and to describe results from patient interviews on their understanding of the term urgency.

METHODS

A retrospective analysis of clinical trial data in patients with D-IBS was conducted. Analyses focused on the relationship of urgency to stool frequency and consistency. Interviews were conducted with patients with D-IBS to test their understanding of the term urgency.

RESULTS

On the days that patients reported urgency, as compared to the days that patients did not report urgency, they had more frequent bowel movements (3.9 versus 1.8) and looser stools (Bristol Stool Score: 5.4 versus 4.2). The differences for both parameters, evaluated on the days with or without urgency, were statistically significant. In patient interviews, patients with D-IBS had a clear understanding of the concept and terminology of urgency and considered it one of their two most bothersome symptoms.

CONCLUSIONS

Urgency should be considered a suitable co-primary endpoint in D-IBS studies.

The development and validation of the daily electronic Endometriosis Pain and Bleeding Diary

Background

The objective of this study was to develop and validate a daily electronic Endometriosis Pain and Bleeding Diary (EPBD) for assessing treatment-related changes in endometriosis symptoms from the patient's perspective in a clinical trial setting.

Methods

The EPBD items were developed based on clinician input and the results of 5 focus groups (N = 38) and 3 iterative sets of cognitive interviews (N = 22). The psychometric properties were evaluated using data collected in a usual-practice, non-intervention study conducted at 4 sites in the United States. Existing questionnaires were also administered to explore the construct validity of the EPBD. The development and validation processes were consistent with the recommendations in the 2009 FDA Patient Reported Outcomes Guidance to Industry.

Results

Focus group participants described 2 distinct types of pain (intermittent and continuous), which they felt were relevant and important to monitor. Participants also indicated that pain and bleeding/spotting associated with intercourse were important symptoms related to endometriosis. Cognitive interviews with additional endometriosis patients served to optimize item content, wording, and response options. Psychometric analyses found the EPBD items to behave as expected, for example, item-level means for subjects with severe endometriosis symptoms were higher (i.e., worse) compared with subjects with mild symptoms. Item-total correlations for the EPBD pain items (range 0.40-0.89) indicated that the items were related but not redundant. EPBD pain ratings correlated highly with the modified Brief Pain Inventory-Short Form Pain Intensity score (range 0.46-0.61). Women with severe endometriosis symptoms reported significantly higher intermittent and continuous dysmenorrhea and intermittent and continuous pelvic pain ratings and greater interference with daily activities compared with women with mild symptoms (all p < 0.01).

Conclusions

The results of this study show that the 17-item EPBD reliably and validly characterizes the types of pain that endometriosis patients identified as being important. As a daily patient-reported assessment, it overcomes the significant potential for intra- and inter-rater variability and rater and recall bias that is inherent in the Biberoglu and Behrman Scale. Additional studies are required to confirm the dimensionality and optimal scoring of the EPBD, to corroborate the present results, and to assess other important measurement properties, such as responsiveness.

Development and psychometric evaluation of the Endometriosis Treatment Satisfaction Questionnaire

PURPOSE

To develop and psychometrically evaluate the Endometriosis Treatment Satisfaction Questionnaire, a patient-reported assessment of satisfaction with endometriosis treatment.

METHODS

The Endometriosis Treatment Satisfaction Questionnaire was developed based on the results of five focus groups and three iterative sets of cognitive interviews along with expert opinion and a review of the literature. The psychometric properties were assessed using data collected during a multicenter, randomized, proof-of-concept trial. The development and validation processes followed the guidance recommended by the United States FDA for patient-reported outcome instruments.

RESULTS

The Endometriosis Treatment Satisfaction Questionnaire's reliability, validity, and utility as a measure of patient satisfaction with their endometriosis treatment were supported. The results of the item-level analyses showed no evidence of distributional anomalies or response scale biases. The Endometriosis Treatment Satisfaction Questionnaire is unidimensional, has excellent internal consistency reliability, and discriminates well between known groups. Scores correlated well with other patient-reported outcome measures of endometriosis without being redundant.

CONCLUSIONS

The Endometriosis Treatment Satisfaction Questionnaire has utility for assessing patient satisfaction with endometriosis treatment and may be useful in clinical trials that are assessing new treatments for endometriosis, especially when deciding between competing treatments or regimens that are found to have similar tolerability and efficacy.

Prevalence and impact of antidepressant-associated sexual dysfunction in three European countries: replication in a cross-sectional patient survey

Sexual dysfunction is a common but often unrecognized side effect of many antidepressants. Building upon the results of a previous investigation, this study aimed to assess the prevalence and impact of antidepressant-associated sexual dysfunction (AASD) in three European countries. A cross-sectional survey of 704 adults in Germany, Spain, and The Netherlands was used in the study. All participants had recently started taking a selective serotonin reuptake inhibitor or serotonin- noradrenaline reuptake inhibitor. Information about other medications and conditions known to impair sexual functioning was gathered, and changes in sexual functioning and the impact of such changes were assessed. The SF-12 and Arizona Sexual Experience Scale (ASEX) were administered to measure health status and sexual functioning. AASD was defined using ASEX scores and information regarding changes in sexual functioning. ASEX scores generally exceeded the threshold defining sexual dysfunction: 67.2% in the German, 79.4% in the Spanish, and 73.3% in the Dutch samples. The prevalence of AASD was conservatively estimated to be between 37.1% (German sample) and 61.5% (Spanish sample). Overall, 46.4% of male and 52.1% of female participants were classified with AASD. Patients classified with AASD reported significantly worse quality of life (QoL), self-esteem, mood, and relationships with partners, compared with non-AASD patients. There were significant differences between patients with and without AASD in SF-12 Mental Component scores, with AASD patients displaying poorer mental well-being. Sexual dysfunction is a frequent occurrence during antidepressant treatment, and is associated with reduced QoL and self-esteem, and negative effects on mood and relationships.

Development and psychometric evaluation of the Bipolar Functional Status Questionnaire (BFSQ)

OBJECTIVES

Persistently impaired psychosocial functioning has been recognized in many individuals with bipolar disorder. However, existing measures of functional disability have been adapted for use in bipolar disorder based mainly on those developed for use in other conditions. The present study involved the development and validation of a new patient self-report measure specific to bipolar disorder, the Bipolar Functional Status Questionnaire (BFSQ).

METHODS

Relevant constructs were identified, evaluated, and refined through an expert advisory panel in conjunction with patient interviews. Questionnaire items were vetted through iterative patient interviews. Psychometric properties were determined based on patient responses from implementation of the proposed 33-item questionnaire in an 11-site study of 596 patients with bipolar disorder across varied phases of illness.

RESULTS

Eight constructs were identified as fundamental to functional status in bipolar disorder: cognitive function, sleep, role functioning, emotional functioning, energy/vitality, social functioning, personal management, and sexual functioning. Psychometric validation supported item reduction to a 24-item unidimensional scale, with high internal consistency (coefficient alpha's = 0.93-0.95), high test-retest reliability (intraclass correlation coefficient = 0.86, 95% confidence interval = 0.82-0.89), strong convergent validity with other functional disability measures (r's > 0.70), and highly significant discriminant validity across illness phases, with large effect sizes (Cohen's d > 0.70).

CONCLUSIONS

The BFSQ is a psychometrically sound self-report measure that can be used to effectively quantify functional status across different clinical states in patients with bipolar disorder.

Design of treatment trials in irritable bowel syndrome: opioid agonists and atypical benzodiazepine antagonists

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain and altered bowel function. Few agents are available for the treatment of IBS. Historically, one impediment to the development of agents to treat IBS was lack of a uniform and robust clinical trial design. Studies occurred with different durations of treatment, endpoints and with different target populations. Great advances have been made over the past decade in trial design including: optimal duration of study, mode of data collection, populations to evaluate and identification of endpoints. Using these refinements, it was possible to demonstrate the efficacy of some new agents. These advances are illustrated by a review of trials with kappa opioid agonists and atypical benzodiazepine antagonists, which appear to be promising new classes of treatments for symptoms in IBS.

Development and evaluation of the Daily Assessment of Symptoms - Anxiety (DAS-A) scale to evaluate onset of symptom relief in patients with generalized anxiety disorder

BACKGROUND

Fast-acting anxiolytics are important to patients and society. Measuring early onset, however, requires a sensitive and clinically responsive measure. This study develops and evaluates the psychometric properties of a new patient-reported instrument, the Daily Assessment of Symptoms - Anxiety (DAS-A), designed to detect reduction of anxiety symptoms in patients with Generalized Anxiety Disorder (GAD) during the first week of treatment.

METHODS

Clinician interviews and patient focus groups were conducted to identify relevant constructs; discussions focused on early symptom improvement and meaningful changes in GAD symptoms. The draft questionnaire underwent iterative sets of cognitive interviews to inform item reduction and revision. A double-blind, randomized, placebo-controlled study of paroxetine and lorazepam assessed the performance of the new instrument in GAD patients. Analyses evaluated the structure, reliability, validity, and utility of the instrument.

RESULTS

There was consistency across focus groups and clinicians in the description of symptoms that improve first. The final item set was easily understood by interview participants. Factor analyses indicated that a unidimensional structure best described the data. Item-level descriptive statistics, Cronbach's alphas, effect sizes, and validity correlations with other scales were favorable. Most importantly, the DAS-A demonstrated separation of lorazepam from placebo within 24h of first dose and correlated with other anxiety measures.

CONCLUSIONS

This study resulted in the development of a reliable and valid instrument addressing the DSM-IV dimensions of GAD. The DAS-A is capable of detecting reduction in anxiety symptoms within 24h, making it a desirable measure to include in future trials of fast-acting anxiety medications.

Gastrointestinal side effects in chronic opioid users: results from a population-based survey

BACKGROUND

Gastrointestinal side effects are commonly associated with opioid treatment for pain.

AIM

To understand gastrointestinal side effects associated with opioid treatment.

METHODS

This study was a population-based survey of adults in the US who use opioids to manage pain unrelated to cancer. Participants were recruited from an existing Web-enabled panel and a supplemental panel of individuals who previously indicated an interest in participating in Web-based surveys.

RESULTS

Overall, 2055 individuals participated in the main phase of the survey. Fifty-seven per cent of participants reported having had constipation that they associated with opioid treatment, and 49% reported constipation in the previous 4 weeks. Thirty-six per cent of participants reported new or worsening constipation in the previous 4 weeks. Thirty-three per cent of participants reported constipation as their most bothersome symptom associated with opioid treatment, 13% reported nausea, 11% abdominal pain and 10% gas. Seventy-three per cent of the participants who reported any GI symptoms did not change the dosage level or frequency of use of opioids because of adverse events, which may be explained by the fact that 72% of participants used over-the-counter laxatives and 12% a prescription laxative.

CONCLUSION

Constipation is a frequent and significant event occurring with opioid use.

Development and preliminary validation of the Menopause Symptoms Treatment Satisfaction Questionnaire (MS-TSQ)

OBJECTIVE

The Menopause Symptoms Treatment Satisfaction Questionnaire, an eight-item questionnaire with a 4-week recall period, was developed to assess women's satisfaction with treatment for symptoms associated with menopause. We describe the development and initial testing of the scale.

DESIGN

Following standard instrument-development procedures, focus groups were conducted with menopausal women experiencing hot flushes to generate potential constructs. Multiple items were drafted to address each construct. An iterative process of cognitive testing, item revision, and item reduction was followed to identify the most appropriate items and optimal response scales. The psychometric validation of the questionnaire used data collected through a multicenter, randomized, double-blind, placebo-controlled study including 543 postmenopausal women. Psychometric analyses were conducted to explore potential item reduction and to address questionnaire scaling and scoring. Internal consistency reliability, construct validity, and discriminant validity of the new scale were also examined.

RESULTS

The questionnaire includes items addressing the control of daytime and nighttime hot flushes; effects of treatment on sleep, mood, libido, and cognition; medication tolerability; and overall satisfaction. Correlation analyses indicated that the items are related to each other without being overly redundant and that the item set is best described using a one-factor model. The subsequent scale score demonstrated sound internal consistency reliability, strong construct validity, and good discriminant validity.

CONCLUSIONS

The results of the development and initial validation are favorable. It is expected that the questionnaire will prove to be a worthwhile tool for assessing women's satisfaction with treatment for menopausal symptoms.

Primary endpoints for irritable bowel syndrome trials: a review of performance of endpoints

The choice of primary endpoint for a clinical trial is one of the most important determinants of the ability of a clinical trial to demonstrate efficacy of therapeutic agents. Although there are still no clear, universally accepted guidelines on the definition of clinical benefit for irritable bowel syndrome (IBS), consensus guidelines stress the importance of using validated endpoints. This article reviews the evidence available in the literature on the psychometric validation and performance of the 3 endpoints recommended by the Rome III Committee for use as primary endpoints in treatment trials of IBS. The Rome III Committee recommends 2 types of measures: binary endpoints addressing the construct of relief (that is, adequate relief and satisfactory relief) and an integrative symptom questionnaire that addresses the change in severity of a representative group of symptoms of IBS (that is, the IBS Severity Scale). The current evidence suggests that at present, adequate relief should be recognized by regulatory authorities as an acceptable primary endpoint in clinical trials. This analysis also suggests that data from individual clinical trials should be pooled and undergo meta-analysis, and that prospective studies should be considered to further characterize the performance of available endpoints as outcome measures in pharmacotherapeutic trials in IBS.

An assessment of patient preference and adherence to treatment with Wellbutrin SR: a web-based survey

BACKGROUND

Research has shown that lack of treatment adherence is a serious problem, especially among patients with psychiatric disorders. The current study was conducted to assess adherence and patient preference among individuals taking Wellbutrin SR (bupropion) for depression, as well as their interest in a once-daily formulation of bupropion.

METHODS

A 20-item web-based survey was administered to 527 individuals (276 men and 251 women) recruited through an online panel. All participants were at least 18 years of age, diagnosed with major depressive disorder, and had been taking Wellbutrin SR for at least 6 weeks. Survey items addressed treatment regimen, adherence, satisfaction with Wellbutrin SR, and interest in a once-daily formulation of bupropion.

RESULTS

The majority of respondents reported taking Wellbutrin SR twice a day (67%). Only 15% of once-daily users were nonadherent compared to 37% of twice-daily users and 65% of thrice-daily users. The most common reason reported for missing a dose of Wellbutrin SR was simply forgetting to take it (49% of twice-daily users and 65% of thrice-daily users). Results indicated that 77% of twice-daily users and 94% of thrice-daily users were interested in a once-daily formula.

CONCLUSIONS

A reduction in dosing frequency is favored by Wellbutrin SR users and likely to improve their adherence to treatment. Because greater adherence has been shown to facilitate symptom relief, improvements in quality of life, and reductions in healthcare expenses, the results of this study support the value of the recently released once-daily formulation, Wellbutrin XL.

Estimating the prevalence and impact of antidepressant-induced sexual dysfunction in 2 European countries: a cross-sectional patient survey

OBJECTIVE

Sexual dysfunction is a common side effect of antidepressant treatment, but recognition of the problem is variable. The aim of this study was to estimate the prevalence and impact of sexual dysfunction during antidepressant treatment in 2 European countries.

METHOD

A cross-sectional survey of 502 adults in France and the United Kingdom. All participants were diagnosed with depression and taking a selective serotonin reuptake inhibitor (SSRI) or serotonin-norepinephrine reuptake inhibitor (SNRI), starting within the previous 3 months. Information was gathered about other medications and conditions known to impair sexual functioning, recent changes in sexual functioning, and the impact of any changes. The Medical Outcomes Study 12-Item Short-Form Health Survey and the Arizona Sexual Experience Scale were administered to measure health status and sexual functioning. Data were collected from June to July of 2002.

RESULTS

Applying a prevalence estimate algorithm, 26.6% of the French sample and 39.2% of the U.K. sample were classified as having antidepressant-induced sexual dysfunction; 34.2% of men and 32.5% of women were classified with antidepressant-induced sexual dysfunction. There was no clear pattern of antidepressant-induced sexual dysfunction related to specific antidepressants. Patients with antidepressant-induced sexual dysfunction reported that changes in sexual functioning negatively affected their self-esteem, mood, and relationships with sexual partners. 23.8% of the French sample and 25.2% of the U.K. sample reported that they perceived that their partner was dissatisfied with their sex life.

CONCLUSION

The prevalence of antidepressant-induced sexual dysfunction in this study is similar to previous estimates reported in the literature. The impact of antidepressant-induced sexual dysfunction is substantial and negatively affects quality of life, self-esteem, mood, and relationships with sexual partners.

The validity and utility of the BPI interference measures for evaluating the impact of osteoarthritic pain

The psychometric properties of the Brief Pain Inventory (BPI), a widely used measure of pain and its impact on functioning, were assessed using data from two clinical trials of controlled-release oxycodone in osteoarthritis (OA) patients. Specifically, the pain-related functional interference subscale and the sleep item from that subscale were examined. In Study 1 (n = 133), "night awakenings with pain" was positively correlated with the BPI interference score and sleep item and both correlated negatively with "quality of sleep." In Study 2 (n = 107), pain experienced "at night while in bed" correlated higher with sleep interference than with the BPI interference subscale. Intraclass correlations denoted adequate test-retest reliability; moderate-to-large Guyatt's statistics provided evidence of responsiveness. These analyses address a gap in the literature regarding the psychometric properties of the BPI interference measures in noncancer pain patients, confirming their reliability, validity, and responsiveness as potential endpoints in trials of pain medications involving patients with OA.

The development and psychometric evaluation of the Motivation and Energy Inventory (MEI)

Because depressed patients commonly experience reductions in motivation and energy, both as symptoms of their disorder and as side effects of pharmacotherapy, it is important to identify interventions that can restore their vitality. The Motivation and Energy Inventory (MEI) was recently developed to facilitate the evaluation of such efforts both in depression research, as well as in other therapeutic areas where vitality is an important issue. The constructs addressed by the MEI were identified through a combination of literature review, consultation with experts, and patient focus groups. Potential problems identified during cognitive testing and addressed in subsequent revisions related to the instructions, reference period, response scale sizes, and response scale labels, as well as a number of item-specific issues. Most recently, the data from two randomized, placebo-controlled clinical trials were utilized to evaluate the psychometric properties of the new questionnaire. In general, the data collected during the first and second trial were used for exploratory and confirmatory analysis, respectively. Consistent with the measurement model of the MEI, the psychometric results confirm that the instrument has three factors generally addressing physical energy, mental energy, and social motivation. Furthermore, these results provide evidence for the internal consistency, construct validity, and responsiveness of all three MEI subscales. Additional work is currently underway to examine test-retest reliability and establish minimal clinically important difference values for the MEI subscales.

Development and validation of the Diabetic Foot Ulcer Scale-short form (DFS-SF)

BACKGROUND

The Diabetic Foot Ulcer Scale (DFS) provides comprehensive measurement of the impact of diabetic foot ulcers on patients' QOL through self-administration of 64 items comprising 15 subscales.

OBJECTIVE

To develop and evaluate a short form of the DFS (DFS-SF) to reduce patient burden and the number of outcome measures, and to improve sensitivity to change in clinical condition.

METHODS

The DFS-SF was created through the analysis of data from a double-blind, placebo-controlled, randomised trial of the efficacy and safety of becaplermin (recombinant human platelet-derived growth factor BB) in the treatment of chronic, full-thickness, neuropathic, diabetic foot ulcers. Using these data, items demonstrating poor psychometric properties were eliminated. Exploratory factor analyses were then conducted to develop a new, more parsimonious scaling algorithm that optimised the internal consistency of the new subscales. Finally, data from two additional clinical trials were used to assess replicability of the DFS-SF subscale structure.

RESULTS

The DFS-SF contains a total of 29 items comprising six subscales. The results of both confirmatory and exploratory factor analyses provided support for the scaling algorithm. The DFS-SF subscales showed good internal consistency, reliability and construct validity, and demonstrated sensitivity to ulcer healing.

CONCLUSIONS

The results of this investigation indicate that the DFS-SF has good psychometric properties and replicability.

Evaluating minimal clinically important differences for the acne-specific quality of life questionnaire

BACKGROUND

The Acne-Specific Quality of Life Questionnaire (Acne-QoL) is a responsive, reliable and valid instrument developed to measure the impact of facial acne across four dimensions of patient QOL. Score changes on this instrument have been used to report statistically significant treatment advantages for a low-dose oral contraceptive (Estrostep, containing norethisterone (norethindrone) acetate (NA) 1mg and ethinylestradiol (EE) [20, 30, 35 mg] as compared with placebo in women with moderate acne vulgaris. However, the question remained if these statistically significant results were also clinically meaningful.

OBJECTIVES

To evaluate the statistically significant Acne-QoL benefits observed with NA/EE in terms of their clinical significance, and to compare the three different approaches for defining a minimal clinically important difference (MCID) for the Acne-QoL instrument.

METHODS

Since the optimum method for estimating MCIDs has yet to be established, three different published approaches for determining MCIDs were applied and compared using data from two randomised, double-blind, placebo- controlled studies of the efficacy of NA/EE in the treatment of facial acne.

RESULTS

Although the approaches differed substantially, the resulting MCID estimates were comparable. Specifically, the MCID estimates ranged from 0.50-10.3 mean change per item, depending on the domain. The results showed that the statistically significant treatment advantages for NA/EE were also clinically significant.

CONCLUSION

When applied to the change scores present, the results showed that the statistically significant treatment advantages for NA/EE were also clinically significant.

Responsiveness of the Acne-Specific Quality of Life Questionnaire (Acne-QoL) to treatment for acne vulgaris in placebo-controlled clinical trials

The Acne-Specific Quality of Life Questionnaire (Acne-QoL) was developed to measure the impact of facial acne across four dimensions of patient quality of life. The main objective of the current study was to evaluate the responsiveness of this instrument. Secondarily, this study provided an opportunity to extend the developer's psychometric validation. The Acne-QoL was utilized in two randomized, double-blind, placebo-controlled studies of the efficacy of Estrostep (norethindrone acetate/ethinyl estradiol) in the treatment of facial acne; a total of 296 Estrostep and 295 placebo patients were evaluated. The Acne-QoL was completed at the beginning, middle (cycle 3), and end (cycle 6) of the 6-month treatment period. The responsiveness of the Acne-QoL was demonstrated through its ability to detect both small (baseline to mid-study) and moderate (baseline to study end) treatment advantages for Estrostep patients. Confirmatory factor analysis supported the subscale structure, and internal consistency estimates were excellent. Convergent and discriminant validity were supported by correlations between Acne-QoL scores and clinical measures that were both in the direction and relative magnitude hypothesized. Finally, item response theory analyses confirmed that each item is highly related to its subscale's latent construct and that each subscale is sensitive across a broad range of the underlying continuum. The results of this evaluation confirm that the Acne-QoL is responsive, internally consistent, and valid.

Accounting for age differences on the Wisconsin Card Sorting Test: decreased working memory, not inflexibility

Two experiments examined the role of cognitive inflexibility and reduced working memory in age-related declines on the Wisconsin Card Sorting Test. Both standard scoring procedures and newly developed scores were used to measure each construct, and modifications of the test further evaluated the role of working memory. Results indicated that age differences are not due to cognitive inflexibility but that for a subset of older adults errors are associated with a reduction in the amount of information that can be stored or processed in working memory. These age differences disappear, however, when visual cues provide information about the immediately preceding sort. The authors conclude by proposing a decline in updating working memory as the explanation that can best account for the entire pattern of age differences on this test.