Sarah Smith

Stroke and Aphasia Quality of Life Scale-39 (SAQOL-39): Evaluation of Acceptability, Reliability, and Validity

Background and Purpose— Health-related quality of life (HRQL) is a key outcome in stroke clinical trials. Stroke-specific HRQL scales (eg, SS-QOL, SIS) have generally been developed with samples of stroke survivors that exclude people with aphasia. We adapted the SS-QOL for use with people with aphasia to produce the Stroke and Aphasia Quality of Life Scale (SAQOL). We report results from the psychometric evaluation of the initial 53-item SAQOL and the item-reduced SAQOL-39. Methods— We studied 95 people with long-term aphasia to evaluate the acceptability, reliability, and validity of the SAQOL and SAQOL-39 using standard psychometric methods. Results— A total of 83 of 95 (87%) were able to complete the SAQOL by self-report; their results are reported here. Results supported the reliability and validity of the overall score on the 53-item SAQOL, but there was little support for hypothesized subdomains. Using factor analysis, we derived a shorter version (SAQOL-39) that identified 4 subdomains (physical, psychosocial, communication, and energy). The SAQOL-39 demonstrated good acceptability, internal consistency (Cronbach’s &agr;=0.74 to 0.94), test-retest reliability (intraclass correlation coefficient=0.89 to 0.98), and construct validity (corrected domain–total correlations, r =0.38 to 0.58; convergent, r =0.55 to 0.67; discriminant, r =0.02 to 0.27 validity). Conclusions— The SAQOL-39 is an acceptable, reliable, and valid measure of HRQL in people with long-term aphasia. Further testing is needed to evaluate the responsiveness of the SAQOL-39 and to investigate its usefulness in evaluative research and routine clinical practice.

Conceptualisation, development, and evaluation of a measure of unplanned pregnancy

Study objective: To develop a measure of unplanned pregnancy that is valid, reliable, and appropriate in the context of contemporary demographic trends and social mores and can be used in a variety of situations, including the production of population prevalence estimates. Design: A two stage study design: qualitative (inductive) methods to delineate the construct of pregnancy planning, and quantitative/psychometric methods to establish the means of measurement. Setting: Eight health service providers (comprising 14 clinics, including antenatal, abortion, and one general practitioner) across London, Edinburgh, Hertfordshire, Salisbury, and Southampton in the UK. Participants: Samples comprised a mixture of pregnant (continuing pregnancy and opting for abortion) and recently pregnant (post-abortion and postnatal) women. At the qualitative stage, 47 women took part in depth interviews (20 of whom were re-interviewed after the birth of their baby). Items were pre-tested with 26 women, and two psychometric field tests were carried out with, respectively, 390 and 651 women. Main results: A six item measure of unplanned pregnancy was produced. Psychometric testing demonstrated the measure’s high reliability (Cronbach’s αu200a=u200a0.92; test-retest reliabilityu200a=u200a0.97) and high face, content, and construct validity. Women’s positions in relation to pregnancy planning are represented by the range of scores (0–12). Conclusions: A psychometric measure of unplanned pregnancy, the development of which was informed by lay views, is now available. The measure is suitable for use with any pregnancy regardless of outcome (that is, birth, abortion, miscarriage) and is highly acceptable to women.

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.

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

BACKGROUNDnWe 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.nnnMETHODnWe 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).nnnRESULTSnDEMQOL 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.nnnCONCLUSIONSnDEMQOL 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.

Predictors of health-related quality of life (HRQL) in people with chronic aphasia

Background: In recent years, quality of life measures have been used increasingly to evaluate the effectiveness of services or interventions. For people with chronic disabilities, research has focused on identifying the main predictors of their health-related quality of life (HRQL), in order to address the issue of how to meet their needs in rehabilitation in a more holistic way. Aims: This study assessed the main predictors of HRQL in people with chronic aphasia following stroke. We investigated the relationship between HRQL and various demographic and stroke-related variables and other variables that have been associated with HRQL in stroke survivors (e.g., emotional distress, daily activities, social support). Methods: A cross-sectional design was adopted. A cluster sampling framework was used to recruit participants with chronic aphasia (> 1 year) from three different sites. Questionnaires and assessments on the different variables were administered to all participants by a speech and language therapist, in an interview format. Multiple regression analysis was used to assess what were the main predictors of HRQL in people with aphasia. Results: Of 95 participants, 83 (87%) were able to self-report on all the assessments. Emotional distress, involvement in home and outdoors activities, extent of communication disability, and number of comorbid conditions explained 52% of the variance in HRQL (adjusted R 2 = .52). Stroke type (infarct vs haemorrhage), time post-onset, and demographic variables (gender, ethnicity, marital status, employment status, and socioeconomic status) were not significantly associated with HRQL in these participants. Conclusions: Increased distress, reduced involvement in activities, increased communication disability, and comorbidity predict poorer HRQL in people with chronic aphasia after stroke. Service providers need to take these factors into account when designing intervention programmes.

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

BACKGROUNDnDementia 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.nnnOBJECTIVESnThe 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.nnnDATA SOURCESnIn 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.nnnREVIEW METHODSnThis 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.nnnRESULTSnAll 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.nnnLIMITATIONSnThe 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.nnnCONCLUSIONnThe 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.nnnFUNDINGnThe National Institute for Health Research Health Technology Assessment programme.

Efficacy of Pimobendan in the Prevention of Congestive Heart Failure or Sudden Death in Doberman Pinschers with Preclinical Dilated Cardiomyopathy (The PROTECT Study)

Background The benefit of pimobendan in delaying the progression of preclinical dilated cardiomyopathy (DCM) in Dobermans is not reported. Hypothesis That chronic oral administration of pimobendan to Dobermans with preclinical DCM will delay the onset of CHF or sudden death and improve survival. Animals Seventy-six client-owned Dobermans recruited at 10 centers in the UK and North America. Methods The trial was a randomized, blinded, placebo-controlled, parallel group multicenter study. Dogs were allocated in a 1:1 ratio to receive pimobendan (Vetmedin capsules) or visually identical placebo. The composite primary endpoint was prospectively defined as either onset of CHF or sudden death. Time to death from all causes was a secondary endpoint. Results The proportion of dogs reaching the primary endpoint was not significantly different between groups (P = .1). The median time to the primary endpoint (onset of CHF or sudden death) was significantly longer in the pimobendan (718 days, IQR 441–1152 days) versus the placebo group (441 days, IQR 151–641 days) (log-rank P = 0.0088). The median survival time was significantly longer in the pimobendan (623 days, IQR 491–1531 days) versus the placebo group (466 days, IQR 236–710 days) (log-rank P = .034). Conclusion and Clinical Importance The administration of pimobendan to Dobermans with preclinical DCM prolongs the time to the onset of clinical signs and extends survival. Treatment of dogs in the preclinical phase of this common cardiovascular disorder with pimobendan can lead to improved outcome.

Psychometric properties of the Stroke and Aphasia Quality of Life Scale (SAQOL-39) in a generic stroke population

Background: We previously developed the Stroke and Aphasia Quality of Life scale (SAQOL-39) and tested it with people with chronic aphasia. A scale allowing comparisons of quality of life between people with versus without aphasia post-stroke would be of value to clinicians. Objectives: To evaluate the psychometrics of the SAQOL-39 in a generic stroke sample. Should this process result in a generic-stroke version of the scale (SAQOL-39g), a further aim is to compare the latter and the SAQOL-39 as tested in chronic aphasia. Design and subjects: Repeated measures psychometric study, evaluating internal consistency, test—retest reliability, construct validity and responsiveness to change. People admitted to hospital with a first stroke were assessed two weeks, three months and six months post stroke. Measures: SAQOL-39, National Institutes of Health Stroke Scale, Barthel, Frenchay Aphasia Screening Test, General Health Questionnaire-12 and Frenchay Activities Index. Results: Of 126 eligible participants, 96 (76%) participated and 87 (69%) were able to self-report and are presented here. Testing the SAQOL-39 in generic stroke resulted in the SAQOL-39g, which has the same items as the SAQOL-39 but three domains: physical, psychosocial, communication. The SAQOL-39g showed good internal consistency (α = 0.95 overall score, 0.92—0.95 domains), test—retest reliability (interclass correlation (ICC) = 0.96 overall, 0.92—0.98 domains), convergent (r = 0.36—0.70 overall, 0.47—0.78 domains) and discriminant validity (r = 0.26 overall, 0.03—0.40 domains). It differentiated people by stroke severity and visual analogue scale (VAS)-defined quality of life. Moderate changes (d = 0.35—0.49; standardized response mean (SRM) = 0.29—0.53) from two weeks to six months supported responsiveness. Conclusions: The SAQOL-39g demonstrated good reliability, validity and responsiveness to change. It can be used to evaluate quality of life in people with and without aphasia post stroke.

Estimating Preference-Based Single Index Measures for Dementia Using DEMQOL and DEMQOL-Proxy

OBJECTIVEnAlthough condition-specific measures are commonly used in dementia, they cannot be used in analyses of cost per quality-adjusted life-year because they do not incorporate preferences. We addressed this gap by estimating two preference-based single index measures: the DEMQOL-U from the self-report DEMQOL (mild-to-moderate dementia severity) and the DEMQOL-Proxy-U from the carer-report DEMQOL-Proxy (all levels of dementia severity).nnnMETHODSnWe conducted valuation studies on 593 members of the general population (306 for the DEMQOL-U, 287 for the DEMQOL-Proxy-U) using the time trade-off elicitation technique. We then fitted a range of mean and individual-level multivariate regression models to the valuation data to derive preference weights for each measure. We applied the estimated weights to a large, clinically representative sample.nnnRESULTSnMean observed time trade-off values ranged from 0.18 to 0.95 for DEMQOL-U and from 0.33 to 0.96 for DEMQOL-Proxy-U. The best performing models for each measure were main effects models estimated using individual-level data. DEMQOL-Proxy-U had inconsistent but insignificant coefficient estimates for one dimension. Models were estimated to remove these inconsistencies.nnnCONCLUSIONnPreference-based single index measures from DEMQOL and DEMQOL-Proxy for use in economic evaluation will enable economic evaluation using quality-adjusted life-years to be undertaken for people across the full range of dementia severity. Future research will examine how the utilities from each measure can be used and combined to populate cost-effectiveness models.

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 (nu200a=u200a420), glaucoma (nu200a=u200a120), diabetic retinopathy, or age related macular degeneration (nu200a=u200a120) and normal controls (nu200a=u200a120). 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 (nu200a=u200a120) 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.