Development of DEMQOL-U and DEMQOL-PROXY-U: generation of preference-based indices from DEMQOL and DEMQOL-PROXY for use in economic evaluation.

BACKGROUND: Dementia is one of the most common and serious disorders in later life and the economic and personal cost of caring for people with dementia is immense. There is a need to be able to evaluate interventions in dementia using cost-effectiveness analyses, but the generic preference-based measures typically used to measure effectiveness do not work well in dementia. Existing dementia-specific measures can effectively measure health-related quality of life but in their current form cannot be used directly to inform cost-effectiveness analysis using quality-adjusted life-years as the measure of effectiveness. OBJECTIVES: The aim was to develop two brief health-state classifications, one from DEMQOL and one from DEMQOL-Proxy, to generate health states amenable to valuation. These classification systems consisted of items taken from DEMQOL and DEMQOL-Proxy so they can be derived from any study that has used these instruments. DATA SOURCES: In the first stage of the study we used a large, clinically representative sample aggregated from two sources: a sample of patients and carers attending a memory service in south London and a sample of patients and carers from other community services in south London. This included 644 people with a diagnosis of mild/moderate dementia and 689 carers of those with mild/moderate dementia. For the valuation study, the general population sample of 600 respondents was drawn to be representative of the UK general population. Households were sampled in urban and rural areas in northern England and balanced to the UK population according to geodemographic profiles. In the patient/carer valuation study we interviewed a sample of 71 people with mild dementia and 71 family carers drawn from a memory service in south London. Finally, the instruments derived were applied to data from the HTA-SADD (Study of Antidepressants for Depression in Dementia) trial. REVIEW METHODS: This was a complex multiphase study with four linked phases: phase 1 - derivation of the health-state classification system; phase 2 - general population valuation survey and modelling to produce values for every health state; phase 3 - patient/carer valuation survey; and phase 4 - application of measures to trial data. RESULTS: All four phases were successful and this report details this development process leading to the first condition-specific preference-based measures in dementia, an important new development in this field. LIMITATIONS: The first limitation relates to the lack of an external data set to validate the DEMQOL-U and DEMQOL-Proxy-U classification systems. Throughout the development process we have made decisions about which methodology to use. There are other valid techniques that could be used and it is possible to criticise the choices that we have made. It is also possible that the use of a mild to moderate dementia sample has resulted in classification systems that do not fully reflect the challenges of severe dementia. CONCLUSION: The results presented are sufficiently encouraging to recommend that the DEMQOL instruments be used alongside a generic measure such as the European Quality of Life-5 Dimensions (EQ-5D) in future studies of interventions in dementia as there was evidence that they can be more sensitive for patients at the milder end of disease and some limited evidence that the person with dementia measure may be able to reflect deterioration. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Applying mixed methods to pretest the Pressure Ulcer Quality of Life (PU-QOL) instrument.

PURPOSE: Pretesting is key in the development of patient-reported outcome (PRO) instruments. We describe a mixed-methods approach based on interviews and Rasch measurement methods in the pretesting of the Pressure Ulcer Quality of Life (PU-QOL) instrument. METHODS: We used cognitive interviews to pretest the PU-QOL in 35 patients with pressure ulcers with the view to identifying problematic items, followed by Rasch analysis to examine response options, appropriateness of the item series and biases due to question ordering (item fit). We then compared findings in an interactive and iterative process to identify potential strengths and weaknesses of PU-QOL items, and guide decision-making about further revisions to items and design/layout. RESULTS: Although cognitive interviews largely supported items, they highlighted problems with layout, response options and comprehension. Findings from the Rasch analysis identified problems with response options through reversed thresholds. CONCLUSIONS: The use of a mixed-methods approach in pretesting the PU-QOL instrument proved beneficial for identifying problems with scale layout, response options and framing/wording of items. Rasch measurement methods are a useful addition to standard qualitative pretesting for evaluating strengths and weaknesses of early stage PRO instruments.

Measuring health-related quality of life in diabetic peripheral neuropathy: a systematic review.

We undertook a systematic review of disease-specific measures of health-related quality of life (HRQL) in diabetic peripheral neuropathy (DPN) to appraise the scientific (psychometric) evidence and make recommendations about the best instrument(s) to use. DPN is a common complication of diabetes mellitus. A need to consider the broad impact of DPN, rather than just pain and the increasingly recognised need to assess patient-reported outcomes such as HRQL in evaluating healthcare has led to a demand for rigorous outcome measures. To identify appropriate disease-specific measures, we searched four databases: PubMed, Embase, PsycINFO and CINAHL Plus. Data were extracted from each article using a standard data extraction form and the psychometric properties of each HRQL measure were reviewed. We identified three DPN-specific measures of HRQL: PN-QOL-97, Norfolk QOL-DN, NeuroQoL. All three measures satisfy at least one criterion for both reliability and validity, though all also have some disadvantages. Where there is no requirement for multi-language versions, the PN-QOL-97 is a useful instrument. Studies that involve multiple languages would need to use the shorter QOL-DN but would also need to incorporate complementary instruments to address the psychological and emotional impact of DPN.

Identification of risk factors by systematic review and development of risk-adjusted models for surgical site infection.

BACKGROUND: Surgical site infections (SSIs) are complications of surgery that cause significant postoperative morbidity. SSI has been proposed as a potential indicator of the quality of care in the context of clinical governance and monitoring of the performance of NHS organisations against targets. OBJECTIVES: We aimed to address a number of objectives. Firstly, identify risk factors for SSI, criteria for stratifying surgical procedures and evidence about the importance of postdischarge surveillance (PDS). Secondly, test the importance of risk factors for SSI in surveillance databases and investigate interactions between risk factors. Thirdly, investigate and validate different definitions of SSI. Lastly, develop models for making risk-adjusted comparisons between hospitals. DATA SOURCES: A single hospital surveillance database was used to address objectives 2 and 3 and the UK Surgical Site Infection Surveillance Service database to address objective 4. STUDY DESIGN: There were four elements to the research: (1) systematic reviews of risk factors for SSI (two reviewers assessed titles and abstracts of studies identified by the search strategy and the quality of studies was assessed using the Newcastle Ottawa Scale); (2) assessment of agreement between four SSI definitions; (3) validation of definitions of SSI, quantifying their ability to predict clinical outcomes; and (4) development of operation-specific risk models for SSI, with hospitals fitted as random effects. RESULTS: Reviews of SSI risk factors other than established SSI risk indices identified other risk; some were operation specific, but others applied to multiple operations. The factor most commonly identified was duration of preoperative hospital stay. The review of PDS for SSI confirmed the need for PDS if SSIs are to be compared meaningfully over time within an institution. There was wide variation in SSI rate (SSI%) using different definitions. Over twice as many wounds were classified as infected by one definition only as were classified as infected by both. Different SSI definitions also classified different wounds as being infected. The two most established SSI definitions had broadly similar ability to predict the chosen clinical outcomes. This finding is paradoxical given the poor agreement between definitions. Elements of each definition not common to both may be important in predicting clinical outcomes or outcomes may depend on only a subset of elements which are common to both. Risk factors fitted in multivariable models and their effects, including age and gender, varied by surgical procedure. Operative duration was an important risk factor for all operations, except for hip replacement. Wound class was included least often because some wound classes were not applicable to all operations or were combined because of small numbers. The American Association of Anesthesiologists class was a consistent risk factor for most operations. CONCLUSIONS: The research literature does not allow surgery-specific or generic risk factors to be defined. SSI definitions varied between surveillance programmes and potentially between hospitals. Different definitions do not have good agreement, but the definitions have similar ability to predict outcomes influenced by SSI. Associations between components of the National Nosocomial Infections Surveillance risk index and odds of SSI varied for different surgical procedures. There was no evidence for effect modification by hospital. Estimates of SSI% should be disseminated within institutions to inform infection control. Estimates of SSI% across institutions or countries should be interpreted cautiously and should not be assumed to reflect quality of medical care. Future research should focus on developing an SSI definition that has satisfactory psychometric properties, that can be applied in everyday clinical settings, includes PDS and is formulated to detect SSIs that are important to patients or health services. FUNDING: The National Institute for Health Research Technology Assessment programme.

Economic burden and cost determinants of deep vein thrombosis during 2 years following diagnosis: a prospective evaluation.

BACKGROUND: Few studies have evaluated the long-term economic consequences of deep vein thrombosis (DVT). None of them have incorporated prospectively collected clinical data to ensure accurate identification of incident cases of DVT and DVT-related health outcomes of interest, such as post-thrombotic syndrome (PTS). OBJECTIVES: To prospectively quantify medical and non-medical resource use and costs related to DVT during 2 years following diagnosis, and to identify clinical determinants of costs. METHODS: Three hundred and fifty-five consecutive patients with acute DVT were recruited at seven Canadian hospital centers. Resource use and cost information were retrieved from three sources: weekly patient-completed cost diaries, nurse-completed case report forms, and the Quebec provincial administrative healthcare database (RAMQ). RESULTS: The rate of DVT-related hospitalization was 3.5 per 100 patient-years (95% confidence interval [CI] 2.2-4.9). Patients reported a mean (standard deviation) of 15.0 (14.5) physician visits and 0.7 (1.2) other healthcare professional visits. The average cost of DVT was $5180 (95% CI $4344-6017) in Canadian dollars, with 51.6% of costs being attributable to non-medical resource use. Multivariate analysis identified four independent predictors of costs: concomitant pulmonary embolism (relative increase in cost [RIC] 3.16; 95% CI 2.18-4.58), unprovoked DVT (RIC 1.65; 95% CI 1.28-2.13), development of PTS during follow-up (RIC 1.35; 95% CI 1.05-1.74), and management of DVT in the inpatient setting (RIC 1.79; 95% CI 1.33-2.40). CONCLUSIONS: The economic burden of DVT is substantial. The use of measures to prevent the occurrence of PTS and favoring outpatient care of DVT has the potential to diminish costs.

The Vascular Access Questionnaire: assessing patient-reported views of vascular access.

BACKGROUND: The use of central venous catheters for vascular access in hemodialysis (HD) patients is associated with an increased risk of complications compared to arteriovenous fistulas (AVF). Despite this, catheter use remains high and patient satisfaction may be an important driver of catheter use. METHODS: We developed the Vascular Access Questionnaire (VAQ) to measure patient-reported views of their vascular access. Chronic HD patients at two centers were asked to rate how bothered they were by 17 access-related problems. VAQ symptom scores were compared between patients using catheters and those using fistulas for vascular access. RESULTS: Two hundred and twenty-two patients were eligible for the study. Symptom score was not different between patients using catheters and those using fistulas (p=0.36). However, patients using fistulas were more likely to be at least moderately bothered by pain, bleeding, bruising, swelling, and the appearance of their access than patients using catheters. Elderly patients reported lower symptom scores with catheters than fistulas. CONCLUSIONS: Patients appear to be primarily concerned with the appearance of their access and cannulation-related complications, particularly the elderly. Better education about the risk of adverse events with catheters and the implementation of measures aimed at reducing cannulation-related complications may help to increase fistula rates and improve patient satisfaction with their vascular access.

Determinants of health-related quality of life during the 2 years following deep vein thrombosis.

BACKGROUND/OBJECTIVES: We prospectively measured change in quality of life (QOL) during the 2 years after a diagnosis of deep vein thrombosis (DVT) and evaluated determinants of QOL, including development of the post-thrombotic syndrome (PTS). PATIENTS/METHODS: Consecutive patients with acute DVT were recruited from 2001 to 2004 at eight hospitals in Canada. At study visits at baseline, and 1, 4, 8, 12 and 24 months, clinical data were collected, standardized PTS assessments were performed, and QOL questionnaires were self-completed. Generic QOL was measured using the Short-Form Health Survey-36 (SF-36) questionnaire. Venous disease-specific QOL was measured using the Venous Insufficiency Epidemiological and Economic Study (VEINES)-QOL/Sym questionnaire. The change in QOL scores over a 2-year follow-up was assessed. The influence of PTS and other characteristics on QOL at 2 years was evaluated using multivariable regression analyses. RESULTS: Among the 387 patients recruited, the average age was 56 years, two-thirds were outpatients, and 60% had proximal DVT. The cumulative incidence of PTS was 47%. On average, QOL scores improved during follow-up. However, patients who developed PTS had lower scores at all visits and significantly less improvement in QOL over time (P-values for PTS*time interaction were 0.001, 0.012, 0.014 and 0.006 for PCS, MCS, VEINES-QOL and VEINES-Sym). Multivariable regression analyses showed that PTS (P < 0.0001), age (P = 0.0009), proximal DVT (P = 0.01) and inpatient status (P = 0.04) independently predicted 2-year SF-36 PCS scores. PTS alone independently predicted 2-year VEINES-QOL (P < 0.0001) and VEINES-Sym (P < 0.0001) scores. CONCLUSIONS: Development of PTS is the principal determinant of health-related QOL 2 years after DVT. Our study provides prognostic information on patient-reported outcomes after DVT and emphasizes the need for effective prevention and treatment of the PTS.

Cost-effectiveness of magnetic resonance-guided focused ultrasound surgery for treatment of uterine fibroids.

OBJECTIVE: To estimate the cost-effectiveness of a treatment strategy for symptomatic uterine fibroids, which starts with Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) as compared with current practice comprising uterine artery embolisation, myomectomy and hysterectomy. DESIGN: Cost-utility analysis based on a Markov model. SETTING: National Health Service (NHS) Trusts in England and Wales. POPULATION: Women for whom surgical treatment for uterine fibroids is being considered. METHODS: The parameters of the Markov model of the treatment of uterine fibroids are drawn from a series of clinical studies of MRgFUS, and from the clinical effectiveness literature. Health-related quality of life is measured using the 6D. Costs are estimated from the perspective of the NHS. The impact of uncertainty is examined using deterministic and probabilistic sensitivity analysis. MAIN OUTCOME MEASURES: Incremental cost-effectiveness measured by cost per quality-adjusted life-year (QALY) gained. RESULTS: The base-case results imply a cost saving and a small QALY gain per woman as a result of an MRgFUS treatment strategy. The cost per QALY gained is sensitive to cost of MRgFUS relative to other treatments, the age of the woman and the nonperfused volume relative to the total fibroids volume. CONCLUSIONS: A treatment strategy for symptomatic uterine fibroids starting with MRgFUS is likely to be cost-effective.

Home care assistance and the utilization of peritoneal dialysis.

Peritoneal dialysis (PD) may be declining because the elderly often have barriers to self-care PD. The objective of this study was to determine whether the availability of home care increases utilization of PD. In 134 incident chronic dialysis patients (median age 73), 108 (81%) had at least one medical or social condition, which was a potential barrier to self-care PD. Eighty percent of patients living in regions where home care was available were considered eligible for PD compared to 65% in regions without home care (P=0.01, adjusted). Each barrier reduced the probability of being eligible for PD by 26% (odds ratio 0.74, per condition, P=0.02) adjusted for age, sex, predialysis care, in-patient start, and availability of home care. In regions with and without home care, 59 and 58% of eligible patients choose PD when they were offered it (P=NS). The utilization of PD in the incident end-stage renal disease (ESRD) population living in regions with and without home care was 47 and 37%, respectively (P=0.27). The mean rate of home care visits over the first year was 4.3 per week (maximum available was 14 per week). Of the 22 assisted patients, 15 required chronic support, five graduated to self-care, and two started with self-care but later required assistance. Adverse events were similar between assisted PD and traditional modalities. Barriers to self-care PD are very common in the elderly ESRD population but home care assistance significantly increases the number of patients who can be safely offered PD.

Development of a new measure of health-related quality of life for people with dementia: DEMQOL.

BACKGROUND: We identified the need to develop a scientifically rigorous measure of health-related quality of life (HRQL) in dementia that would be appropriate for use at all stages of dementia severity and would be available in both self- and proxy-report versions. METHOD: We used standard psychometric methods to eliminate items with poor psychometric properties (item-reduction field test) and to assess the acceptability, reliability and validity of the item-reduced instruments (psychometric evaluation field test). We developed and validated two versions of DEMQOL: a 28-item interviewer-administered questionnaire that is self-reported by the person with dementia (DEMQOL) and a 31-item interviewer-administered questionnaire that is proxy-reported by a caregiver (DEMQOL-Proxy). RESULTS: DEMQOL shows high reliability (internal consistency and test-retest) and moderate validity in people with mild/moderate dementia. DEMQOL-Proxy shows good acceptability and internal consistency and moderate evidence of validity in people with mild/moderate and severe dementia. Test-retest reliability and performance in people with severe dementia need further testing. CONCLUSIONS: DEMQOL and DEMQOL-Proxy show psychometric properties that are comparable with the best available dementia-specific measures of HRQL. We recommend that DEMQOL and DEMQOL-Proxy are used together. Reliability and validity need to be confirmed in independent samples and responsiveness needs to be evaluated.

The Patient Outcomes of Surgery-Head/Neck (POS-head/neck): a new patient-based outcome measure.

OBJECTIVES: To develop a new patient-based outcome measure in plastic surgery for head/neck skin lesions for use in audit, clinical trials and effectiveness studies. DESIGN AND SUBJECTS: Questionnaire development and validation study. Qualitative methods, including interviews with 27 patients, were carried out to develop a preliminary version of the questionnaire. The questionnaire was then field tested by postal survey of 141 pre- and 250 post-surgery patients to produce a shortened (item-reduced) questionnaire and to evaluate acceptability, reliability, validity and responsiveness. A second field test was carried out by postal survey in an independent sample of 67 pre-surgery patients to further evaluate the reliability and validity of the questionnaire. MAIN OUTCOME MEASURES: Psychometric properties of acceptability, reliability, validity, and responsiveness were assessed. RESULTS: We developed a new measure, the Patient Outcomes of Surgery-Head/Neck (POS-Head/Neck), which includes a six- and nine-item pre- and post-surgery questionnaire, respectively. Results confirmed the acceptability (missing data <10%, evenly distributed endorsement frequencies), reliability (Cronbach alphas >0.76, item-total correlations >0.22), validity (scale inter-correlations r=0.50, scaling assumptions, correlations with age and sex < -0.25) and responsiveness (effect size=0.63) of the questionnaire. CONCLUSIONS: The POS-Head/Neck is a new surgical outcome measure that can be used to evaluate outcomes in malignant and benign head/neck skin lesions before and after surgery is acceptable to patients and satisfies rigorous scientific criteria.

Quality of life in dementia: more than just cognition. An analysis of associations with quality of life in dementia.

OBJECTIVES: To explore the extent to which commonly used measures of specific outcomes in dementia are an appropriate proxy for quality of life in dementia. METHODS: This was a cross sectional study set in communities in London and Nottingham, comprising 101 people with dementia and their 99 main family caregivers. The main outcome measures were health related quality of life in dementia (measured by the DEMQOL-Proxy), cognition (Mini Mental State Examination), functional impairment (Barthel Index), behavioural and psychological symptoms in dementia (Neuropsychiatric Inventory; NPI), and carer mental health (General Health Questionnaire). RESULTS: On univariate analysis, decreased quality of life was statistically significantly correlated with higher levels of behavioural and psychological disturbance (NPI total score and its agitation, depression, anxiety, disinhibition, and irritability subscales); younger age of the person with dementia; and poorer mental health of the carer. Quality of life was not statistically significantly associated with cognition or carer age. In a multivariate model, psychological and behavioural disturbance and patient age remained statistically significantly associated with quality of life. Carer mental health was no longer statistically significantly associated, and cognition and functional limitation remained statistically insignificant. CONCLUSIONS: These data suggest that quality of life in dementia is complex, and that simple proxy substitutions of discrete measures such as cognition or function are likely to miss important factors.

How responsive is the Multiple Sclerosis Impact Scale (MSIS-29)? A comparison with some other self report scales.

OBJECTIVES: To compare the responsiveness of the Multiple Sclerosis Impact Scale (MSIS-29) with other self report scales in three multiple sclerosis (MS) samples using a range of methods. To estimate the impact on clinical trials of differing scale responsiveness. METHODS: We studied three discrete MS samples: consecutive admissions for rehabilitation; consecutive admissions for steroid treatment of relapses; and a cohort with primary progressive MS (PPMS). All patients completed four scales at two time points: MSIS-29; Short Form 36 (SF-36); Functional Assessment of MS (FAMS); and General Health Questionnaire (GHQ-12). We determined: (1) the responsiveness of each scale in each sample (effect sizes): (2) the relative responsiveness of competing scales within each sample (relative efficiency): (3) the differential responsiveness of competing scales across the three samples (relative precision); and (4) the implications for clinical trials (samples size estimates scales to produce the same effect size). RESULTS: We studied 245 people (64 rehabilitation; 77 steroids; 104 PPMS). The most responsive physical and psychological scales in both rehabilitation and steroids samples were the MSIS-29 physical scale and the GHQ-12. However, the relative ability of different scales to detect change in the two samples was variable. Differing responsiveness implied more than a twofold impact on sample size estimates. CONCLUSIONS: The MSIS-29 was the most responsive physical and second most responsive psychological scale. Scale responsiveness differs notably within and across samples, which affects sample size calculations. Results of clinical trials are scale dependent.

An evaluation of the costs, effectiveness and quality of renal replacement therapy provision in renal satellite units in England and Wales.

OBJECTIVES: To survey of the structure, processes and organisation of renal satellite units (RSUs) in England and Wales (Phase 1), and to compare the effectiveness, acceptability, accessibility and economic impact of chronic haemodialysis performed in RSUs compared to main renal units (MRUs) (Phase 2). DATA SOURCES: Phase 1: all renal satellite units in England and Wales. Phase 2: haemodialysis patients in a representative sample (based on geography, site, private--public ownership, medical input) of 12 RSUs and their MRUs. REVIEW METHODS: Phase 1 consisted of a questionnaire survey. Semi-structured interviews were held in a representative sample of 24 RSUs with the senior clinician, senior nurse and manager. Phase 2 consisted of a cross-sectional comparison of patients in these RSUs and patients in the parent MRUs deemed suitable for satellite care by senior staff. Clinical information was obtained from medical notes and unit computer systems. Generic and disease specific health-related quality of life (HRQoL) measures were used. Co-morbidity was assessed by the Wright/Khan Index, the Lister/Chandna score, the Modified Charlson Index, and the Karnofsky Performance Score. Statistical analyses compared RSU versus MRU patients and took account of the paired and clustered nature of the data. RESULTS: In Phase 1, responses were received from 74/80 (93%) of RSUs; 2600 patients were being treated in these RSUs. The interviews were generally positive about the impact of RSUs in terms of improved accessibility and a better environment for chronic haemodialysis (HD) patients, and in expanding renal replacement therapy patients (RRT) capacity. In Phase 2, some 82% of eligible patients took part, 394 patients in the 12 RSUs and 342 in the parent MRUs. The response rate was similar in both groups. There were no significant differences in clinical processes of care. Most clinical outcomes were similar, especially after pooled analysis, although a few parameters were statistically significantly different -- notably the proportion achieving Renal Association Standards for adequacy of dialysis as measured by the urea reduction ratio (URR) was higher in the RSU patients. Patient-specific quality of life did not differ except on the patient satisfaction questions from the KDQOL, which were scored higher by the RSU sample. Strength of preference for health status on and off dialysis was very similar between the groups, as were EQ-5D utilities. Major adverse events were not common in the RSU patients, although there were many hypotensive episodes on HD, a proportion of which affected the duration of the HD session. Of the costs measured, the only difference that was statistically significant was for District Nurse visits. Of particular note was that despite the MRU group having a higher proportion of patients hospitalised, this did not translate into a statistically significant budgetary impact in terms of the total cost per patient of hospitalisations or mean cost per patient per hospitalisation. CONCLUSIONS: This study has shown that RSUs are an effective alternative to MRU HD for a wide spectrum of patients. They improve geographic access for more dispersed areas and reduce patients' travel time, and are generally more acceptable to patients on several criteria. There does not seem to be an adverse impact of care in the RSUs although comparative long-term prospective data are lacking. The evidence suggests that satellite development could be successfully expanded; not all MRUs have any satellites and many have only a few. No single RSU model can be recommended but key factors would include local geography, the likely catchment population and the type of patients to be treated. There is a need for more basic budgetary information linking activity and expenditure to be available and more transparent, to perform at least an insightful top-down costing of the two care settings. Other areas suggested for further research include: a comparison of adverse events occurring in MRUs and RSUs with longer duration and larger numbers to identify more severe events, along with the more research into the scope for preventing such events, and a study into the patients deemed ineligible for satellite care. International comparisons of satellite care would also be useful.

The development of the Indian vision function questionnaire: field testing and psychometric evaluation.

OBJECTIVE: To develop and evaluate the acceptability, reliability, validity, and responsiveness of the Indian vision function questionnaire (IND-VFQ). METHODS: Problem statements from previous qualitative studies were reduced to a 45 item interviewer administered questionnaire representing three a priori domains (general functioning, psychosocial impact, and visual symptoms) which was evaluated in patients with cataract (n = 420), glaucoma (n = 120), diabetic retinopathy, or age related macular degeneration (n = 120) and normal controls (n = 120). Standard methods were used for item reduction and to evaluate psychometric properties. RESULTS: Psychometric item reduction produced a 33 item questionnaire. Psychometric evaluation showed that two of the three scales (psychosocial impact and visual symptoms) had good acceptability, and that all three scales showed high internal consistency (alpha >0.80; item-total correlations 0.54-0.86) and test-retest reliability (>0.89). All three scales showed moderate evidence of convergent and discriminant validity. Responsiveness, assessed in cataract patients (n = 120) before and after surgery, was good for all three scales (effect sizes >1). CONCLUSIONS: The IND-VFQ33 is a psychometrically sound measure of vision function addressing a gap in patient defined measures of vision function developed in populations living in low income countries.

Measurement of health-related quality of life for people with dementia: development of a new instrument (DEMQOL) and an evaluation of current methodology.

OBJECTIVES: To develop and validate a psychometrically rigorous measure of health-related quality of life (HRQoL) for people with dementia: DEMQOL. DATA SOURCES: Literature review. Expert opinion. Interviews and questionnaires. REVIEW METHODS: Gold standard psychometric techniques were used to develop DEMQOL and DEMQOL-Proxy. A conceptual framework was generated from a review of the literature, qualitative interviews with people with dementia and their carers, expert opinion and team discussion. Items for each component of the conceptual framework were drafted and piloted to produce questionnaires for the person with dementia (DEMQOL) and carer (DEMQOL-Proxy). An extensive two-stage field-testing was then undertaken of both measures in large samples of people with dementia (n = 130) and their carers (n = 126) representing a range of severity and care arrangements. In the first field test, items with poor psychometric performance were eliminated separately for DEMQOL and DEMQOL-Proxy to produce two shorter, more scientifically robust instruments. In the second field test, the item-reduced questionnaires were evaluated along with other validating measures (n = 101 people with dementia, n = 99 carers) to assess acceptability, reliability and validity. RESULTS: Rigorous evaluation in two-stage field testing with 241 people with dementia and 225 carers demonstrated that in psychometric terms: (1) DEMQOL is comparable to the best available dementia-specific HRQoL measures in mild to moderate dementia, but is not appropriate for use in severe dementia [Mini Mental State Examination (MMSE) <10]; and (2) DEMQOL-Proxy is comparable to the best available proxy measure in mild to moderate dementia, and shows promise in severe dementia. In addition, the DEMQOL system has been validated in the UK in a large sample of people with dementia and their carers, and it provides separate measures for self-report and proxy report, which allows outcomes assessment across a wide range of severity in dementia. CONCLUSIONS: The 28-item DEMQOL and 31-item DEMQOL-Proxy provide a method for evaluating HRQoL in dementia. The new measures show comparable psychometric properties to the best available dementia-specific measures, provide both self- and proxy-report versions for people with dementia and their carers, are appropriate for use in mild/moderate dementia (MMSE >/= 10) and are suitable for use in the UK. DEMQOL-Proxy also shows promise in severe dementia. As DEMQOL and DEMQOL-Proxy give different but complementary perspectives on quality of life in dementia, the use of both measures together is recommended. In severe dementia, only DEMQOL-Proxy should be used. Further research with DEMQOL is needed to confirm these findings in an independent sample, evaluate responsiveness, investigate the feasibility of use in specific subgroups and in economic evaluation, and develop population norms. Additional research is needed to address the psychometric challenges of self-report in dementia and validating new dementia-specific HRQoL measures.

The influence of venous thromboembolism on quality of life and severity of chronic venous disease.

BACKGROUND: It is not known whether burden-of-illness differs in chronic venous disease patients with prior venous thromboembolism compared with patients with other forms of chronic venous disease. OBJECTIVE: To compare severity of disease and quality of life in chronic venous disease patients with and without prior venous thromboembolism. PATIENTS AND METHODS: The VEINES Study population is an international cohort of 1531 outpatients with chronic venous disease in Belgium, France, Italy and Canada. Clinical severity of chronic venous disease graded using the seven-category 'CEAP' scale, and quality of life using standardized generic (SF-36) and venous disease-specific (VEINES-QOL/Sym) questionnaires were compared in patients with and without venous thromboembolism. Multivariable analyses with adjustment for known confounders were used to examine associations between venous thromboembolism and quality of life. RESULTS: One hundred and fifty-one (10%) patients had prior venous thromboembolism. These patients had more severe chronic venous disease than those without venous thromboembolism (P <0.0001), including a higher frequency of healed or active ulcers (29% vs. 7%, respectively). Multivariable analyses controlling for age, sex, country, education, body mass index, years of chronic venous disease and comorbid conditions demonstrated that prior venous thromboembolism was an independent predictor of poorer generic quality of life (SF-36 Mental Component Summary score, P=0.047; SF-36 Physical Component Summary score, P=0.012) and venous disease-specific quality of life (VEINES-QOL, P = 0.0002; VEINES-Sym, P=0.009). CONCLUSIONS: Disease severity is worse and quality of life poorer in chronic venous disease patients with prior venous thromboembolism compared with patients with other forms of chronic venous disease. Our findings support the need for further research of interventions to prevent and treat the long-term complications of venous thromboembolism.

Coronary revascularisation outcome questionnaire (CROQ): development and validation of a new, patient based measure of outcome in coronary bypass surgery and angioplasty.

OBJECTIVE: To describe the development and scientific validation of a new patient based measure, the coronary revascularisation outcome questionnaire (CROQ), to evaluate health outcomes and quality of life before and after coronary artery bypass grafting and percutaneous transluminal coronary angioplasty. DESIGN AND SETTING: Psychometric validation study conducted with patients from three hospitals in the UK. PATIENTS: Two independent field tests were conducted by postal survey of 714 patients before and 1329 patients after coronary revascularisation to evaluate the measurement properties of the CROQ. METHODS: Qualitative methods including patient interviews were used to develop questionnaire content. A full psychometric evaluation was performed on the survey data. RESULTS: Psychometric tests with the application of stringent criteria confirmed the acceptability (low missing data, good response rates), scaling assumptions (good item convergent and discriminant validity), reliability (good internal consistency and reproducibility), validity (good content and construct validity), and responsiveness of the CROQ. CONCLUSIONS: The CROQ is a practical and scientifically sound patient based measure of outcome developed using psychometric methods. It captures aspects of recovery not addressed in other cardiac questionnaires and has been shown to be a highly responsive instrument that will be useful in evaluating outcomes in clinical trials.

The Patient Outcomes of Surgery-Hand/Arm (POS-Hand/Arm): a new patient-based outcome measure.

The purpose of this study was to develop and validate a new patient-based outcome measure for hand/arm disorders for use in audit, clinical trials and effectiveness studies. There were three stages. First, we carried out interviews with 40 patients with hand/arm disorders to develop and pilot questionnaire content. Second, in a postal survey with 165 pre- and 181 post-surgery patients, we reduced the number of items and identified scales. Third, in a postal survey with 132 pre- and 204 post-surgery patients we evaluated the psychometric properties of the measure. Findings confirmed the acceptability, reliability, validity and responsiveness to clinical change of the questionnaire. The Patient Outcomes of Surgery-Hand/Arm (POS-Hand/Arm) is a new surgical outcome measure that can be used before and after surgery (29 and 33 items, respectively) to evaluate and compare new techniques, surgical teams and units.