Measuring agreement between patient and proxy responses to multidimensional health-related quality-of-life measures in clinical trials. An application of psychometric profile analysis

Are We Agreed? Self- Versus Proxy-Reporting of Paediatric Health-Related Quality of Life (HRQoL) Using Generic Preference-Based Measures: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this study was to examine the level of agreement between self- and proxy-reporting of health-related quality of life (HRQoL) in children (under 18 years of age) using generic preference-based measures.

METHODS

A systematic review of primary studies that reported agreement statistics for self and proxy assessments of overall and/or dimension-level paediatric HRQoL using generic preference-based measures was conducted. Where available, data on intraclass correlation coefficients (ICCs) were extracted to summarise overall agreement levels, and Cohen's kappa was used to describe agreement across domains. A meta-analysis was also performed to synthesise studies and estimate the level of agreement between self- and proxy-reported paediatric overall and domain-level HRQoL.

RESULTS

Of the 30 studies included, 25 reported inter-rater agreement for overall utilities, while 17 reported domain-specific agreement. Seven generic preference-based measures were identified as having been applied: Health Utilities Index (HUI) Mark 2 and 3, EQ-5D measures, Child Health Utility 9 Dimensions (CHU9D), and the Quality of Well-Being (QWB) scale. A total of 45 dyad samples were included, with a total pooled sample of 3084 children and 3300 proxies. Most of the identified studies reported a poor inter-rater agreement for the overall HRQoL using ICCs. In contrast to more observable HRQoL domains relating to physical health and functioning, the inter-rater agreement was low for psychosocial-related domains, e.g., 'emotion' and 'cognition' attributes of both HUI2 and HUI3, and 'feeling worried, sad, or unhappy' and 'having pain or discomfort' domains of the EQ-5D. Parents demonstrated a higher level of agreement with children relative to health professionals. Child self- and proxy-reports of HRQoL showed lower agreement in cancer-related studies than in non-cancer-related studies. The overall ICC from the meta-analysis was estimated to be 0.49 (95% confidence interval 0.34-0.61) with poor inter-rater agreement.

CONCLUSION

This study provides evidence from a systematic review of studies reporting dyad assessments to demonstrate the discrepancies in inter-rater agreement between child and proxy reporting of overall and domain-level paediatric HRQoL using generic preference-based measures. Further research to drive the inclusion of children in self-reporting their own HRQoL wherever possible and limiting the reliance on proxy reporting of children's HRQoL is warranted.

Optimal Methods for Reducing Proxy-Introduced Bias on Patient-Reported Outcome Measurements for Group-Level Analyses

BACKGROUND

Caregivers, or proxies, often complete patient-reported outcomes (PROs) on behalf of patients; yet, research has demonstrated proxies rate patient outcomes worse than patients rate their own outcomes. To improve interpretability of PROs in group-level analyses, our study aimed to identify optimal approaches for reducing proxy-introduced bias in the analysis of PROs.

METHODS

Data were simulated based on 200 patients with stroke and their proxies who both completed 9 PROMIS domains as part of a cross-sectional study. The sample size was varied as 50, 100, 200, and 500, and the proportion of patients with proxy-respondents was varied as 10%, 20%, and 50%. Six methods for handling proxy-completions were investigated: (1) complete case analysis; (2) proxy substitution; (3) Method 2 plus proxy adjustment; (4) Method 3 including inverse-probability of treatment weighting; (5) multiple imputation; (6) linear equating. These methods were evaluated by comparing average bias in PROMIS T-scores (estimated versus observed patient-only responses), as well as by comparing estimated regression coefficients to models using patient-only responses.

RESULTS

Overall mean T-score differences ranged from 0 to 1.75. The range of mean differences varied by the 6 methods with methods 1 and 5 providing estimates closest to the observed mean. In regression models, all but inverse-probability of treatment weighting resulted in low bias when proxy-completions were 10% to 20%. With 50% proxy-completions, method 5 resulted in less accurate estimations while methods 1 to 3 provided less proxy-introduced bias. Bias remained low across domain and varying sample sizes but increased with larger percentages of proxy-respondents.

CONCLUSIONS

Our study found modest proxy-introduced bias when estimating PRO scores or regression estimates across multiple domains of health. This bias remained low, even when sample size was 50 and there were large proportions of proxy-completions. While many of these methods can be chosen for including proxies in stroke PRO research with <20% proxy-respondents, proxy substitution with adjustment resulted in low bias with 50% proxy-respondents.

Development of a person-centered interdisciplinary plan-of-care program for dialysis

BACKGROUND

Dialysis care often focuses on outcomes that are of lesser importance to patients than to clinicians. There is growing international interest in individualizing care based on patient priorities, but evidence-based approaches are lacking. The objective of this study was to develop a person-centered dialysis care planning program. To achieve this objective we performed qualitative interviews, responsively developed a novel care planning program and then assessed program content and burden.

METHODS

We conducted 25 concept elicitation interviews with US hemodialysis patients, care partners and care providers, using thematic analysis to analyze transcripts. Interview findings and interdisciplinary stakeholder panel input informed the development of a new care planning program, My Dialysis Plan. We then conducted 19 cognitive debriefing interviews with patients, care partners and care providers to assess the program's content and face validities, comprehensibility and burden.

RESULTS

We identified five themes in concept elicitation interviews: feeling boxed in by the system, navigating dual lives, acknowledging an evolving identity, respecting the individual as a whole person and increasing individualization to enhance care. We then developed a person-centered care planning program and supporting materials that underwent 32 stakeholder-informed iterations. Data from subsequent cognitive interviews led to program revisions intended to improve contextualization and understanding, decrease burden and facilitate implementation.

CONCLUSIONS

My Dialysis Plan is a content-valid, person-centered dialysis care planning program that aims to promote care individualization. Investigation of the program's capacity to improve patient experiences and outcomes is needed.

Patient versus proxy response on global health scales: no meaningful DIFference

PURPOSE

Assessment of outcomes from a proxy is often substituted for the patient's self-report when the patient is unable or unwilling to report their status. Research has indicated that proxies over-report symptoms on the patient's behalf. This study aimed to quantify the extent of proxy-introduced bias on the Patient-Reported Outcomes Measurement Information System Global Health (PROMIS GH) scale for mental (GMH) and physical (GPH) scores.

METHODS

This retrospective cohort study included incident stroke patients seen in a cerebrovascular clinic who completed PROMIS GH between 10/12/15 and 6/6/18. Differential item functioning (DIF) evaluated measurement invariance of patient versus proxy responses. DIF impact was assessed by comparing the initial score to the DIF-adjusted score. Subgroup analyses evaluated DIF within strata of stroke severity, measured by modified Rankin Scale (≤ 1, 2, 3+), and time since stroke (≤ 30, 31-90, > 90 days).

RESULTS

Of 1351 stroke patients (age 60.5 ± 14.9, 45.1% female), proxy help completing PROMIS GH was required by 406 patients (30.1%). Proxies indicated significantly worse response to all items. No items for GMH or GPH were identified as having meaningful DIF. In subgroup analyses, no DIF was found by severity or 31-90 days post-stroke. In patients within 30 and > 90 days of stroke, DIF was detected for 2 items. Accounting for DIF had negligible effects on scores.

CONCLUSIONS

Our findings revealed the overestimation of symptoms by proxies is a real difference and not the result of measurement non-invariance. PROMIS GH items do not perform differently or have spuriously inflated severity estimates when administered to proxies instead of patients.

Validation and reliability of the Abbreviated World Health Organization Quality of Life Instrument (WHOQOL-BREF) in the hospitalized trauma population

INTRODUCTION

While the number of trauma patients surviving their injury increase, it is important to measure Quality of Life (QoL). The Abbreviated World Health Organization Quality of Life (WHOQOL-BREF) questionnaire can be used to assess QoL. However, its psychometric properties in trauma patients are unknown and therefore, we aimed to investigate the validity and reliability of the WHOQOL-BREF for the hospitalized trauma population.

METHODS

Data were derived from the Brabant Injury Outcome Surveillance. Floor and ceiling effects and missing values of the WHOQOL-BREF were examined. Confirmatory factor analysis (CFA) was performed to examine the underlying 4 dimensions (i.e. physical, psychological, social and environmental) of the questionnaire. Cronbach's alpha (CA) was calculated to determine internal consistency. In total, 42 hypotheses were formulated to determine construct validity and 6 hypotheses were created to determine discriminant validity. To determine construct validity, Spearman's correlations were calculated between the WHOQOL-BREF and the EuroQol-five-dimension-3-level questionnaire, the Health Utility Index Mark 2 and 3, the Hospital Anxiety and Depression Scale and the Impact of Event Scale. Discriminant validity between patients with minor injuries (i.e. Injury Severity Score (ISS)≤8) and moderate/severe injuries (i.e. ISS ≥ 9) was examined by conducting Mann-Whitney-U-tests.

RESULTS

In total, 202 patients (median 63y) participated in this study with a median of 32 days (interquartile range 29-37) post-trauma. The WHOQOL-BREF showed no problematic floor and ceiling effects. The CFA revealed a moderate model fit. The domains showed good internal consistency, with the exception of the social domain. All individual items and domain scores of the WHOQOL-BREF showed nearly symmetrical distributions since mean scores were close to median scores, except of the 'general health' item. The highest percentage of missing values was found on the 'sexual activity' item (i.e. 19.3%). The WHOQOL-BREF showed moderate construct and discriminant validity since in both cases, 67% of the hypotheses were confirmed.

CONCLUSION

The present study provides support for using the WHOQOL-BREF for the hospitalized trauma population since the questionnaire appears to be valid and reliable. The WHOQOL-BREF can be used to assess QoL in a heterogeneous group of hospitalized trauma patients accurately.

TRAIL REGISTRATION

ClinicalTrials.gov identifier: NCT02508675.

Cultural adaptation to Spanish (Spain) of the "Overactive Bladder - Family Impact Measure (OAB-FIM)" questionnaire

OBJECTIVE

The OAB-FIM was developed as a measure of the impact of an overactive bladder (OAB) on relatives who live with the patient. The objective of this study was conduct a cultural adaptation to Spanish (Spain) of the OAB-FIM questionnaire.

METHODS

The adaptation included a conceptual and linguistic validation phase, as well as a phase for measuring the psychometric properties in 25 relatives [mean age, 63.0 years (SD, 14.3); 44% women] who regularly live with patients with OAB, who are of either sex and 18 years of age or older. We measured conceptual and linguistic equivalence, internal reliability, construct validity and content validity. We assessed the applicability and administration load.

RESULTS

The OAB-FIM was conceptually and linguistically equivalent to the original, maintaining its 6 domains: social, travel, worry, irritability, sleep and sex. The interagreement correctly placed all items in their domain, except for number 10, which was placed more in worry than in irritability, motivates its reformulation. Some 2.95% of the items were missing. The floor and ceiling effects of the items varied, respectively, between 20-28%, and 0-16%. The mean time for completing the questionnaire was 5.2minutes (SD, 2.8), and 24% of the participants required some type of assistance. The α-Cronbach coefficient varied between 0.948-0.839. The correlations with similar scales in the family were moderate-high (0.407-0.753) or small-moderate with those administered to the patient (0.004-0.423).

CONCLUSION

We obtained a Spanish (Spain) version of the OAB-FIM that was conceptually and linguistically equivalent to the original. The questionnaire showed good internal consistency, content and construct validity and applicability.

Lifetime allergic rhinitis prevalence among US primary farm operators: findings from the 2011 Farm and Ranch Safety survey

PURPOSE

Allergic rhinitis is associated with decreased quality of life, and reduced workplace performance and productivity. This study investigated the prevalence of lifetime allergic rhinitis and factors associated with allergic rhinitis among US primary farm operators.

METHODS

The 2011 Farm and Ranch Safety Survey data collected from 11,210 active farm operators were analyzed. Survey respondents were determined to have lifetime allergic rhinitis based on a "yes" response to the question: "Have you ever been told by a doctor, nurse, or other health professional that you had hay fever, seasonal allergies, or allergic rhinitis?" Data were weighted to produce nationally representative estimates.

RESULTS

An estimated 30.8% of the 2.1 million active farm operators had lifetime allergic rhinitis in 2011. The allergic rhinitis prevalence varied by demographic and farm characteristics. Farm operators with allergic rhinitis were 1.38 (95% CI 1.22-1.56) times more likely to be exposed to pesticides compared with operators with no allergic rhinitis. The association with pesticide exposure for allergic rhinitis and current asthma, and allergic rhinitis alone was statistically significant and greater than that for current asthma alone.

CONCLUSION

Certain groups of farm operators may be at increased risk of allergic rhinitis. Studies should further investigate the association of allergic rhinitis with specific pesticide exposure.

Systematic review of caregiver responses for patient health-related quality of life in adult cancer care

PURPOSE

In surveys and in research, proxies such as family members may be used to assess patient health-related quality of life. The aim of this research is to help cancer researchers select a validated health-related quality of life tool if they anticipate using proxy-reported data.

METHODS

Systematic review and methodological appraisal of studies examining the concordance of paired adult cancer patient and proxy responses for multidimensional, validated HRQOL tools. We searched PubMed, CINAHL, PsycINFO and perused bibliographies of reviewed papers. We reviewed concordance assessment methods, results, and associated factors for each validated tool.

RESULTS

A total of 32 papers reporting on 29 study populations were included. Most papers were cross-sectional (N = 20) and used disease-specific tools (N = 19), primarily the FACT and EORTC. Patient and proxy mean scores were similar on average for tools and scales, with most mean differences <10 points but large standard deviations. Average ICCs for the FACT and EORTC ranged from 0.35 to 0.62, depending on the scale. Few papers (N = 15) evaluated factors associated with concordance, and results and measurement approaches were inconsistent. The EORTC was the most commonly evaluated disease-specific tool (N = 5 papers). For generic tools, both concordance and associated factor information was most commonly available for the COOP/WONCA (N = 3 papers). The MQOL was the most frequently evaluated end-of-life tool (N = 3 papers).

CONCLUSIONS

Proxy and patient scores are similar on average, but there is large, clinically important residual variability. The evidence base is strongest for the EORTC (disease-specific tools), COOP/WONCA (generic tools), and MQOL (end-of-life-specific tools).

Reliability in Measuring Preinjury Physical Function in Orthopaedic Trauma

OBJECTIVE

In orthopaedic trauma, patients' functional status scores cannot be collected before injury. Due to the lack of these data, it is difficult to reliably determine if patients have returned to their preinjury level of physical function. The goal of this article is to determine if patients' assessment of preinjury function agrees with that of familiar proxies, to determine whether patient assessment of preinjury function may be regarded as reliable.

METHODS

At first postinjury outpatient follow up, orthopaedic trauma patients and their proxies were asked to independently complete the PROMIS physical function computer adaptive test (PF CAT) based on how they perceived the function of the patient before injury. Intraclass correlation, paired sample t tests, and 95% confidence intervals were used to analyze patient-proxy agreement.

RESULTS

Fifty patient-proxy pairs completed the questionnaire at an average of 14.3 (SD = 1.1) days postoperative (average 19.3, SD = 12.1 days postinjury). Patient mean PF CAT score was 57.92 (SD = 10.38) for patients and 56.59 (SD = 11.50) for proxies. Paired samples t test showed that patient's PF CAT scores were not significantly different from proxy scores [mean score difference = 1.33; 95% CI = (-1.28, 3.94); P = 0.311]. Intraclass correlation between patient and proxy scores was 0.79. There was no notable bias.

DISCUSSION

Good agreement in PF CAT preinjury assessment between patients and proxies support patients' ability to report reliable preinjury physical functioning in the early postinjury setting using the PF CAT.

Agreement Between Responses From Community-Dwelling Persons With Stroke and Their Proxies on the NIH Neurological Quality of Life (Neuro-QoL) Short Forms

OBJECTIVE

To examine agreement between patient and proxy responses on the Quality of Life in Neurological Disorders (Neuro-QoL) instruments after stroke.

DESIGN

Cross-sectional observational substudy of the longitudinal, multisite, multicondition Neuro-QoL validation study.

SETTING

In-person, interview-guided, patient-reported outcomes.

PARTICIPANTS

Convenience sample of dyads (N=86) of community-dwelling persons with stroke and their proxy respondents.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Dyads concurrently completed short forms of 8 or 9 items for the 13 Neuro-QoL adult domains using the patient-proxy perspective. Agreement was examined at the scale-level with difference scores, intraclass correlation coefficients (ICCs), effect size statistics, and Bland-Altman plots, and at the item-level with kappa coefficients.

RESULTS

We found no mean differences between patients and proxies on the Applied Cognition-General Concerns, Depression, Satisfaction With Social Roles and Activities, Stigma, and Upper Extremity Function (Fine Motor, activities of daily living) short forms. Patients rated themselves more favorably on the Applied Cognition-Executive Function, Ability to Participate in Social Roles and Activities, Lower Extremity Function (Mobility), Positive Affect and Well-Being, Anxiety, Emotional and Behavioral Dyscontrol, and Fatigue short forms. The largest mean patient-proxy difference observed was 3 T-score points on the Lower Extremity Function (Mobility). ICCs ranged from .34 to .59. However, limits of agreement showed dyad differences exceeding ±20 T-score points, and item-level agreement ranged from not significant to weighted kappa=.34.

CONCLUSIONS

Proxy responses on Neuro-QoL short forms can complement responses of moderate- to high-functioning community-dwelling persons with stroke and augment group-level analyses, but do not substitute for individual patient ratings. Validation is needed for other stroke populations.

Do claimants over-report behavioral health dysfunction when filing for work disability benefits?

BACKGROND

Questions exist related to the best way to use medical evidence relative to self-report as part of the SSA disability determination process.

OBJECTIVE

To examine concordance between provider and claimant responses along the four dimensions of work related behavioral health functioning: Social Interactions, Mood and Emotions, Behavioral Control, and Self-Efficacy.

METHODS

Using secondary data from a larger study, which collected data on individuals reporting difficulties with work (claimants) due to mental conditions, 39 items were completed by claimants and their healthcare provider. Inter-rater agreement was assessed using three techniques: Cohen's kappa, percent absolute agreement, and folded mountain plots.

RESULTS

A sample of 65 dyads was obtained. Inter-rater agreement was low for most items (k=0.0-0.20) with a minority of items having fair agreement (k=0.21-0.40) Percent agreement was fair: Mood and Emotions (46%), Self-Efficacy (44%), Behavioral Control (39%) and Social Interactions (38%). Overall, providers reported lower functioning compared to claimants for the Behavioral Control and Self-Efficacy scales; the reverse trend held for the Mood and Emotions scale.

CONCLUSIONS

Results indicate discordance between provider and claimant report of behavioral health functioning. Understanding reasons for and approaches to reconciling the inconsistencies between claimant and provider perspectives is a complex task. These findings have implications for how best to assess mental and behavioral-health related work disability in the absence of an established gold standard measure.

Quality of life before admission to the intensive care unit

Objective

To examine the reliability of the SF-36 general health questionnaire when used to evaluate the health status of critically ill patients before admission to intensive care and to measure their health-related quality of life prior to admission and its relation to severity of illness and length of stay in the intensive care unit.

Methods

Prospective cohort study conducted in the intensive care unit of a public teaching hospital. Over three months, communicative and oriented patients were interviewed within the first 72 hours of intensive care unit admission; 91 individuals participated. The APACHE II score was used to assess severity of illness, and the SF-36 questionnaire was used to measure health-related quality of life.

Results

The reliability of SF-36 was verified in all dimensions using Cronbach's alpha coefficient. In six dimensions of eight domains the value exceeded 0.70. The average SF-36 scores of the health-related quality of life dimensions for the patients before admission to intensive care unit were 57.8 for physical functioning, 32.4 for role-physical, 53.0 for bodily pain, 63.2 for general health, 50.6 for vitality, 56.2 for social functioning, 54.6 for role-emotional and 60.3 for mental health. The correlations between severity of illness and length of stay and the health-related quality of life scores were very low, ranging from -0.152 to 0.175 and -0.158 to 0.152, respectively, which were not statistically significant.

Conclusion

In the sample studied, the SF-36 demonstrated good reliability when used to measure health-related quality of life in critically ill patients before admission to the intensive care unit. The worst score was role-physical and the best was general health. Health-related quality of life of patients before admission was not correlated with severity of illness or length of stay in the intensive care unit.

Measuring the population burden of injuries--implications for global and national estimates: a multi-centre prospective UK longitudinal study

BACKGROUND

Current methods of measuring the population burden of injuries rely on many assumptions and limited data available to the global burden of diseases (GBD) studies. The aim of this study was to compare the population burden of injuries using different approaches from the UK Burden of Injury (UKBOI) and GBD studies.

METHODS AND FINDINGS

The UKBOI was a prospective cohort of 1,517 injured individuals that collected patient-reported outcomes. Extrapolated outcome data were combined with multiple sources of morbidity and mortality data to derive population metrics of the burden of injury in the UK. Participants were injured patients recruited from hospitals in four UK cities and towns: Swansea, Nottingham, Bristol, and Guildford, between September 2005 and April 2007. Patient-reported changes in quality of life using the EQ-5D at baseline, 1, 4, and 12 months after injury provided disability weights used to calculate the years lived with disability (YLDs) component of disability adjusted life years (DALYs). DALYs were calculated for the UK and extrapolated to global estimates using both UKBOI and GBD disability weights. Estimated numbers (and rates per 100,000) for UK population extrapolations were 750,999 (1,240) for hospital admissions, 7,982,947 (13,339) for emergency department (ED) attendances, and 22,185 (36.8) for injury-related deaths in 2005. Nonadmitted ED-treated injuries accounted for 67% of YLDs. Estimates for UK DALYs amounted to 1,771,486 (82% due to YLDs), compared with 669,822 (52% due to YLDs) using the GBD approach. Extrapolating patient-derived disability weights to GBD estimates would increase injury-related DALYs 2.6-fold.

CONCLUSIONS

The use of disability weights derived from patient experiences combined with additional morbidity data on ED-treated patients and inpatients suggests that the absolute burden of injury is higher than previously estimated. These findings have substantial implications for improving measurement of the national and global burden of injury.

Measuring the population burden of fatal and nonfatal injury

The value of measuring the population burden of fatal and nonfatal injury is well established. Population health metrics are important for assessing health status and health-related quality of life after injury and for integrating mortality, disability, and quality-of-life consequences. A frequently used population health metric is the disability-adjusted life-year. This metric was launched in 1996 in the original Global Burden of Disease and Injury study and has been widely adopted by countries and health development agencies alike to identify the relative magnitude of different health problems. Apart from its obvious advantages and wide adherence, a number of challenges are encountered when the disability-adjusted life-year is applied to injuries. Validation of disability-adjusted life-year estimates for injury has been largely absent. This paper provides an overview of methods and existing knowledge regarding the population burden of injury measurement. The review of studies that measured burden of injury shows that estimates of the population burden remain uncertain because of a weak epidemiologic foundation; limited information on incidence, outcomes, and duration of disability; and a range of methodological problems, including definition and selection of incident and fatal cases, choices in selection of assessment instruments and timings of use for nonfatal injury outcomes, and the underlying concepts of valuation of disability. Recommendations are given for methodological refinements to improve the validity and comparability of future burden of injury studies.

Patient-surrogate agreement of predictors of decision delay among patients with acute myocardial infarction: a questionnaire survey

BACKGROUND

Studies that assessed predictors of patient delay to seek healthcare for acute myocardial infarction lack generalization to all patient population as it investigated patients who survived coronary events.

OBJECTIVES

To evaluate utility of using surrogates to proxy patients who cannot be interviewed and to examine patients-surrogate agreement.

DESIGN

A cross-sectional descriptive survey study. The cognitive and emotional domains of the modified Response to Symptoms Questionnaire were used to interview participants.

PARTICIPANTS AND SETTINGS

A convenient sample of patient-surrogate pairs was collected (n=109). Hospitalized patients with acute myocardial infarction were eligible if they were at least 18 years old, hemodynamically stable, pain free or controlled pain during interview, and could identify a surrogate. Exclusions (n=45) were patients transferred from other hospitals or those who had acquired heart attack following their admission. A surrogate was defined as an individual who witnessed the onset of symptoms and whom the patient has articulated symptoms with prior to admission.

METHODS

Patient and surrogate were interviewed independently. Decision delay time was assessed by assisting participants and surrogates to triangulate the time of symptom onset and time of decision to seek help by placing it in the context of events that they would remember. The intraclass correlation coefficient was used to assess agreement.

RESULTS

Patients were mainly men (81%), married (79%) and ranged in age from 39 to 78 years while surrogates were mostly women (74%) and 55% of them were patients' spouses. Surrogates ranged in age from 18 to 75 years. Intraclass correlation coefficients levels varied across different variables ranging from lack of agreement (p>0.05) to almost perfect agreement with decision delay time having the highest correlation coefficient (86%, p<0.05). Cognitive variables had higher agreement than emotional variables. Significant emotional variables' agreement ranged form 28% to 39% and significant cognitive variables' agreement ranged form 64% to 68%. Female surrogates (n=81) had higher agreement levels with their respective patients than male surrogates (n=28).

CONCLUSIONS

Utilizing surrogates to proxy patients' account of decision delay time and its cognitive predictors is practical and feasible.

Validity of proxies and correction for proxy use when evaluating social determinants of health in stroke patients

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate stroke patient-proxy agreement with respect to social determinants of health, including depression, optimism, and spirituality, and to explore approaches to minimize proxy-introduced bias.

METHODS

Stroke patient-proxy pairs from the Brain Attack Surveillance in Corpus Christi Project were interviewed (n=34). Evaluation of agreement between patient-proxy pairs included calculation of intraclass correlation coefficients, linear regression models (ProxyResponse=alpha(0)+alpha(1)PatientResponse+delta, where alpha(0)=0 and alpha(1)=1 denotes no bias) and kappa statistics. Bias introduced by proxies was quantified with simulation studies. In the simulated data, we applied 4 approaches to estimate regression coefficients of stroke outcome social determinants of health associations when only proxy data were available for some patients: (1) substituting proxy responses in place of patient responses; (2) including an indicator variable for proxy use; (3) using regression calibration with external validation; and (4) internal validation.

RESULTS

Agreement was fair for depression (intraclass correlation coefficient, 0.41) and optimism (intraclass correlation coefficient, 0.48) and moderate for spirituality (kappa, 0.48 to 0.53). Responses of proxies were a biased measure of the patients' responses for depression, with alpha(0)=4.88 (CI, 2.24 to 7.52) and alpha(1)=0.39 (CI, 0.09 to 0.69), and for optimism, with alpha(0)=3.82 (CI, -1.04 to 8.69) and alpha(1)=0.81 (CI, 0.41 to 1.22). Regression calibration with internal validation was the most accurate method to correct for proxy-induced bias.

CONCLUSIONS

Fair/moderate patient-proxy agreement was observed for social determinants of health. Stroke researchers who plan to study social determinants of health may consider performing validation studies so corrections for proxy use can be made.

The influence of proxy perspective on patient-proxy agreement in the evaluation of health-related quality of life: an empirical study

AIMS

There are situations in which patient self-reported health-related quality of life must be substituted by proxy assessments. Pickard and Knight recently delineated 2 proxy perspectives that may influence the nature of proxy measurements: the "proxy-patient" (the proxy's assessment from the patient's perspective) and the "proxy-proxy" perspective (the proxy's own assessment of the patient). They argued that the "proxy-patient" perspective would be " optimally consistent with the patient's view." The purpose of this study was to evaluate these to proxy perspectives in terms of patient-proxy bias and agreement.

METHODS

The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 was administered to 224 cancer patients and their proxies (ie, significant others), who were randomly assigned to 1 of the 2 proxy conditions. Differences in patient-proxy bias and agreement were evaluated using t tests, percentage agreement, and intraclass and Pearson correlation coefficients.

RESULTS

Small yet significant amounts of patient-proxy bias were found in both conditions, with patients reporting higher levels of functioning and lower symptoms levels than proxies. However, no significant differences in bias were observed between the conditions. Significantly better agreement on the role and cognitive functioning scales was found in the "proxy-proxy" condition, and for the diarrhea scale in the "proxy-patient" condition.

CONCLUSIONS

There is some indication that several of the European Organization for Research and Treatment of Cancer functional scales may perform better when using the "proxy-proxy" perspective. However, no compelling evidence was found for clear superiority of either proxy perspective. These results deserve further study, as they are not entirely consistent with the pattern of agreement implied by Pickard and Knight.

Patient and spouse perceived quality of life five years after coronary artery bypass graft surgery

Health-related quality of life (HRQoL) was examined in patients’ and their respective spouses’ perspectives five years after cardiac bypass surgery. Participants completed the Short-Form 36 (SF-36) which consists of eight domains and two component summary scores measuring physical and mental HRQoL (PCS and MCS respectively). Paired t tests were used to compare couples responses (n=56 pairs) with spouses recording higher (i.e. better scores) in the physical-related domains although differences were not significant. Statistically significant results were found between patients and spouses in emotional role, mental health, social functioning, energy/vitality and general health perceptions (p< 0.001). The PCS were very similar for both the patient and spouses sample (45.9 v. 45.8 respectively, p = .829) and the MCS was significantly higher in the patients compared to the spouses (54.8 v. 47.7, p < .001). The results demonstrated that spouses could accurately report the physical aspects of HRQoL but not the mental health of their partner.

Development and validation of a measure of the impact of epilepsy on a young person's quality of life: Glasgow epilepsy outcome scale for young persons (GEOS-YP)

OBJECTIVE

The goal of the work described here was to develop and validate a measure of the impact of epilepsy on an adolescent's quality of life that is based on direct exploration of the adolescent's views.

METHODS

Initial scale development was based on data generated through qualitative methods (focus groups) in a previous study [McEwan MJ, Espie CA, Metcalfe J, Brodie MJ, Wilson MT. Seizure 2004;13:15-31]. A draft measure was piloted (n=30) and refined using correlational methods. Psychometric properties were established by means of a preliminary field trial (n=78).

RESULTS

An initial item pool of 76 was refined to 50. The structure of the measure mirrored the conceptual model derived from focus group study; Part 1 covered issues relating to adolescent development (identity formation) with five subscales, and Part 2 covered epilepsy-related issues with four subscales. The final GEOS-YP had good internal consistency (alpha=0.91) and test-retest reliability (rho=0.75). Concurrent and construct validity was acceptable, and the GEOS-YP discriminated on dimensions of clinical importance. Participant feedback suggested the measure has excellent face validity and potential clinical utility.

CONCLUSIONS

The GEOS-YP is a direct measure of how adolescents perceive epilepsy impacts their quality of life. The GEOS-YP has sound psychometric properties and provides a relatively brief and potentially useful clinical outcome tool.

Consistency of quality assessments in long-term care by the clients, family members and named nurses

Combining assessments by the clients, their family members and named nurses of the quality of long-term care leads to a more comprehensive picture of the quality of the service. Clients should be the primary source of information, but particularly when they are not able to express their opinion, other sources of assessment are needed. This study describes and compares the consistency of quality assessments of long-term institutional care for the elderly made by the client (n = 312), his/her family member (n = 312) and the named nurse (n = 312). Data were gathered in 2002 from service houses, nursing homes and health centres. The consistency of the assessments made by the different groups of respondents was measured by frequency distributions, the weighted kappa coefficient and exact agreement. Frequency distributions differed significantly between the respondent groups in almost every item. Family members were more critical in their assessments than the other two groups. The consistency of assessments was highest with regard to the items 'contact with significant others' and 'medication'. In general the consistency of assessments, measured by weighted kappa, was rather low, but it was fair for 'clothing' (clients/family members) and 'privacy' (clients/named nurses and family members/named nurses). The occurrence of the option 'not applicable' to certain items was quite high, but varied somewhat between the three respondent groups. The results of this study support the viewpoint that comprehensive information gathering from family members and named nurses is useful, but they should not replace clients' assessments.

Children proxies' quality-of-life agreement depended on the country using the European KIDSCREEN-52 questionnaire

OBJECTIVE

The aims of this study were to assess the level of agreement and the magnitude of discrepancies between children and their parents, and whether these levels of agreement/discrepancy depend on the country of living, the domains of quality of life assessed, the age and gender of the children, and other background variables.

STUDY DESIGN AND SETTING

The KIDSCREEN pilot study involved 2,526 youth-proxy pairs in seven European countries. The health-related quality of life (HRQoL) of children and their parents as proxy has been assessed in parallel using a 10-dimension KIDSCREEN-52 Pilot test questionnaire.

RESULTS

For the 10 dimensions, the mean difference between proxy and youth score decreases as the HRQoL level increases. Physical and cognitive domains showed the major agreement between youth and proxy measure. Social and psychological domains presented the main discrepancies. Linear regression models highlighted that the agreement was depending on the country for the 10 dimensions. Impact of age and gender on agreement were not consistent across the 10 dimensions.

CONCLUSION

Agreement is higher for the girls than for the boys and for the adolescents than for children. To further explore the country effect on agreement, results need replication in representative studies.

Difference in reported pre-morbid health-related quality of life between ARDS survivors and their substitute decision makers

CONTEXT

Substitute decision makers may consider the pre-morbid health status of their critically ill loved one when making treatment decisions on her/his behalf.

OBJECTIVE

To compare estimates of pre-morbid health-related quality of life (HRQOL) obtained from survivors of the acute respiratory distress syndrome (ARDS) with those of their substitute decision makers using the Short Form 36 (SF-36).

DESIGN

Prospective cohort study.

SETTING

University-affiliated intensive care unit in Toronto, Canada.

PATIENTS

A sample of 46 ARDS survivors and their substitute decision makers drawn from a previously described cohort.

INTERVENTIONS

We measured agreement and differences between responses on the SF-36 obtained from survivors (at 3 months after ICU discharge) and their substitute decision makers (at study entry).

MEASUREMENTS AND RESULTS

Agreement was poor for all SF-36 components and differences reached significance in three domains. In multivariable analysis considering age; sex; Acute Physiology, Age, and Chronic Health Evaluation II score; and Lung Injury Score, only patient age was associated with the mean difference between estimates for the 'Mental Health' domain. On average, estimates of pre-morbid HRQOL obtained from substitute decision makers were lower than those obtained from survivors.

CONCLUSION

Agreement between estimates of pre-morbid HRQOL provided by ARDS survivors and their substitute decision makers was poor. Compared with survivors, proxies tended to provide lower estimates of pre-morbid HRQOL. Substitute decision making for incapacitated patients is an imperfect process during which family members may underestimate their loved ones' own perception of pre-morbid health status. Alternatively, survivors of critical illness may overestimate pre-morbid HRQOL.

Patients' self-report and family caregivers' perception of quality of life in patients with advanced cancer: how do they compare?

This study describes the concordance between advanced cancer patients' self-report of quality of life and their caregivers' perception of the patients' quality of life at two time points. It is often necessary for health professionals to rely on information about the patients' quality of life that is provided by family caregivers (proxy), even though information from the patients is considered 'the gold standard'. Therefore, it is important to establish how reliable this proxy information is. Data were collected 4-6 weeks following diagnosis of recurrent or progressive disease, and again 12 weeks later. Fifty-one patients and their caregivers completed the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30), version 2.0 at both time points. Descriptive statistics were used to calculate patient and caregiver scores and describe the sample. The level of agreement between the two scores, the patients' self-report and the family caregivers' score, was calculated on the mean scores of each scale. In general, most caregivers were able to accurately rate the global quality of life, the level of functioning and the degree of symptom distress experienced by the person they were caring for, when compared with the patients' self-rating. Caregiver ratings for physical domains tended to be more in agreement with those of patients as compared with ratings of the psychosocial domains. This study suggests information from proxy raters is reliable when the proxy is a family caregiver, and this remains true over time.

Development of a measure to assess the impact of epilepsy on people with an intellectual disability: the Glasgow Epilepsy Outcome Scale - Client version (GEOS-C)

BACKGROUND

Epilepsy is common in people with intellectual disability, yet clinicians and researchers seldom obtain information directly from the client. The development and preliminary validation of a novel measure for use with people with mild to moderate intellectual disabilities is described.

METHODS

Focus group methods (6 groups; 24 participants) identified issues of concern, and qualitative analysis (NUD*IST) was applied to derive items and themes for a draft scale. Psychometric scale development techniques were then used in a pilot study and subsequent field-testing to investigate validity and reliability (n = 46).

RESULTS

A total of 148 issues of concern was reduced initially to 52 and then to 42 items using these methods. The derived scale comprised sub-scales reflecting (1) concerns about having seizures; (2) about injury; (3) about issues during; and (4) after seizures; (5) about medication; (6) about what people think; and (7) about daily life. Cronbach alpha for the Glasgow Epilepsy Outcome Scale - Client version (GEOS-C) was 0.92, and ranged from 0.64-0.81 for the sub-scales. Relatively weak associations (r <or= 0.40), between client and family carer, staff carer or clinician views, suggests that proxy reports are not good predictors of how people with epilepsy themselves are feeling. Preliminary validation suggests that the GEOS-C can discriminate on variables of clinical importance.

CONCLUSIONS

The GEOS-C complements existing GEOS measures, can be completed in 5-15 min depending upon the level of support required, and may provide a valuable clinical and research tool. Further validational work and appraisal of sensitivity are required.

Proxy respondents reliably assessed the quality of life of elective cardiac surgery patients

BACKGROUND AND OBJECTIVE

The level of agreement between index and proxy respondents on assessment of health status of clinical cohorts is variable. There is limited information regarding agreement between cardiac surgery patients and their proxies, and levels of agreement examined across repeated measures. This study examined the level of agreement between index and proxy respondents' perceptions of the patient's health status prior to and following cardiac surgery.

METHODS

A prospective, paired-respondent, repeated measures observational study of elective cardiac surgical patients and their next of kin, from the cardiac surgical unit of a tertiary hospital in Sydney, Australia. Health status domains were examined using the15D and SF-36 instruments at three points: prior to surgery, at hospital discharge, and at 6 months post discharge.

RESULTS

Moderate to good level of agreement was noted for physical function (physical functioning, role functioning-physical, mobility, breathing, speech, hearing, usual activities, sexual activities) and some psychosocial dimensions (role functioning-emotional, sleeping, depression, mental health). Agreement was highest for presurgery and 6 months post discharge. Differences in scores were not clinically important.

CONCLUSION

Proxy respondents can reliably assess the quality of life of a cardiac surgical patient using 15D or SF-36, particularly for domains reflecting physical function.

Proxy evaluation of health-related quality of life: a conceptual framework for understanding multiple proxy perspectives

Proxy assessment of health-related quality of life (HRQL) may be sought to substitute for, or to complement, patient self-assessment. The viewpoint from which the proxy is asked to assess the patient is a subtle yet important aspect of proxy assessment. Proxy assessments can be elicited by asking a proxy to assess the patient as they think the patient would respond (ie, proxy-patient perspective) or for the proxy to provide their own perspective on the patient's HRQL (ie, proxy-proxy perspective). In this article, we introduce a framework for differentiating between and understanding HRQL assessments according to rater viewpoint. The difference between patient self-assessment and the proxy-patient perspective is defined as the inter-rater gap, whereas the difference between the proxy-patient and proxy-proxy perspective is described as the intra-proxy gap. The inter-rater gap represents the difference between patient self-assessed HRQL and the proxy ability to comprehend the patient view. The extent to which the proxy-proxy perspective is informative will depend upon the proxy's ability to provide reinforcing or complementary information, ie, represented by the intra-proxy gap, on the HRQL of the patient. We refer to the framework to emphasize the importance of delineating between proxy perspectives in study design and HRQL measurement and to guide inquiries into the validity and interpretation of the meaningfulness of the proxy HRQL assessments from each viewpoint. Future research and use of proxy raters of HRQL in clinical trials, population health monitoring, resource allocation, and clinical management can be informed by explicit consideration of the suggested framework.

Estimating Health-Related Quality of Life in Populations Through Cross-Sectional Surveys

BACKGROUND

Health-related quality of life (HRQL) is optimally reported from the individual vantage point; consequently, prevalence estimates from the National Health Interview Survey (NHIS) could be misleading, because approximately one third of the information is proxy-provided.

OBJECTIVE

The objective of this study was to discern the degree to which disparities in the crude prevalence of reduced HRQL is explainable by case-mix differences between proxy- and self-reportees.

SUBJECTS

We studied the cross-sectional data on 96,091 persons from the 1994-1995 NHIS Supplement on Disability.

RESEARCH DESIGN

We conducted a study of reduced HRQL expressed as a respondent type indicator (proxy vs. self) adjusting for socioeconomic differences and limitations in function.

MEASURES

We studied reduced HRQL indicated by 1) perception of poor health, 2) perception of disability, 3) 30 or more bed days in the last year, or 4) 20 or more doctor visits in the last year.

RESULTS

The crude estimated prevalence of reduced HRQL for proxy reports was approximately half that of self-reports. Although the unadjusted odds ratios (ORs) for proxy- compared with self-reportees ranged from 0.51 (95% confidence interval [CI], 0.47-0.55) to 0.59 (95% CI, 0.55-0.64), case-mix adjustment resulted in a significant directional change for poor health perception, and all adjusted ORs were substantially closer to 1.0 than their unadjusted counterparts.

CONCLUSION

Adjustment for case-mix explained away most of the proxy-/self-report disparity, suggesting that a major component of differences in prevalence between proxy- and self-respondents is case-mix-related. Consequently, compared with excluding proxy reports, inclusion of proxy reports results in relatively less bias when the NHIS-D is applied to obtain prevalence estimates for the indicators studied.

Quality of life and psychosocial development in adolescents with epilepsy: a qualitative investigation using focus group methods

The majority of previous studies investigating the impact of epilepsy on the QOL of adolescents have used proxy opinions from clinicians and/or parents. This study highlights the need for research to investigate QOL from the direct perspective of adolescents and consider issues in the context of a developmental perspective. A focus group technique was used. Twenty-two adolescents aged between 12 years 4 months and 18 years 0 months (6 males and 16 females) were stratified by age (12-13, 14-15 and 16+ years) into six focus groups. Data were transcribed and QSR NUD*IST 4.0 was used to help generate central themes. Several procedures were undertaken to increase validity and reliability of findings. Analysis identified two main themes comprising (a) issues related to adolescent development (identity formation) and (b) epilepsy related variables, with five and four main sub-themes, respectively ('peer acceptance', 'development of autonomy', 'school related issues', 'epilepsy as part of me' and 'future', and 'medication issues', 'seizures', 'knowledge of epilepsy' and 'sense of uncertainty'). The main issues related to peer acceptance and development of autonomy. In contrast to previous studies, academic difficulties were not highlighted as an issue. No significant age-related differences in issues were identified. A conceptual model representing these findings is presented and clinical implications and suggestions for future research are reported.

A systematic review of the contribution of qualitative research to the study of quality of life in children and adolescents with epilepsy

A sizeable literature focusing on QOL in children and adolescents with epilepsy has been produced over the last few years. However, relatively little emphasis has been placed on defining these issues from direct exploration of children's and adolescents' views. Qualitative methodologies are proposed in this review as an appropriate means of eliciting such information. This review systematically investigated the extent to which studies of QOL in children and adolescents with epilepsy have used recognised qualitative methodology. Articles for inclusion were identified by searching the term 'epilepsy', combined with 'adolescent(s) and/or child(ren)' and 'psychosocial and/or quality of life'. Selected articles were reviewed and rated using CASP Guidelines for qualitative research by two independent raters. Seventeen studies were retrieved through literature search. Of these six used some form of qualitative methodology either individually or combined with quantitative methods. However, only one study met quality criteria for selection in this systematic review. A summary of both selected and excluded studies is presented and methodological limitations discussed. Recommendations for appropriate methodology for investigation of QOL issues in children and adolescents are given.

Regular Visitors Are Not Good Substitutes for Assessment of Elderly Patient Satisfaction With Nursing Home Care and Services

BACKGROUND

Due to physical and psychological impairments, elderly patients residing in homes are often unable to participate in studies on satisfaction with care services. While their regular visitors provide interesting information, patient-visitor response concordance requires study. Our objective was to measure patient-visitor agreement on quality of care and accommodation.

METHODS

A survey was conducted on elderly people in 13 nursing homes and their visitors. The 125 patient-visitor pairs completed the same Nursing Home Satisfaction Questionnaire (NHSQ) independently, for which reliability and internal validity have previously been explored. Satisfaction scores for room comfort, meal provision, information, and medical/nursing care were calculated. To estimate patient-visitor concordance, intraclass coefficients, a bias index, and Pearson's correlation coefficients were calculated.

RESULTS

Patient satisfaction scores ranged from 57.8 (information) to 78.6 (room comfort), and visitor satisfaction from 67.9 (meal provision) to 85.9 (medical/nursing care). Mean visitor scores were higher for all scales, with a small-to-moderate index bias statistically significant for medical/nursing care (p <.001), information (p <.001), and meal provision (p =.006). Intraclass correlation coefficients were low for room comfort, information, and medical/nursing care scales (0.08 to 0.18), and nearly acceptable for the meal provision scale (0.46).

CONCLUSIONS

Visitors were not able to provide information on elderly patients' satisfaction with nursing home. Their assessments were milder than patient assessments. The NHSQ is reliable for use in either population, but patient and visitor assessments should not be merged in satisfaction studies.