Validity, responsiveness, and minimal important difference for the SF-6D health utility scale in a spinal cord injured population

Early surgery compared to nonoperative management for mild degenerative cervical myelopathy: a cost-utility analysis

BACKGROUND CONTEXT

Degenerative cervical myelopathy (DCM) is a form of acquired spinal cord compression and contributes to reduced quality of life secondary to neurological dysfunction and pain. There remains uncertainty regarding optimal management for individuals with mild myelopathy. Specifically, owing to lacking long-term natural history studies in this population, we do not know whether these individuals should be treated with initial surgery or observation.

PURPOSE

We sought to perform a cost-utility analysis to examine early surgery for mild degenerative cervical myelopathy from the healthcare payer perspective.

STUDY DESIGN/SETTING

We utilized data from the prospective observational cohorts included in the Cervical Spondylotic Myelopathy AO Spine International and North America studies to determine health related quality of life estimates and clinical myelopathy outcomes.

PATIENT SAMPLE

We recruited all patients that underwent surgery for DCM enrolled in the Cervical Spondylotic Myelopathy AO Spine International and North America studies between December 2005 and January 2011.

OUTCOME MEASURES

Clinical assessment measures were obtained using the Modified Japanese Orthopedic Association scale and health-related quality of life measures were obtained using the Short Form-6D utility score at baseline (preoperative), 6 months, 12 months and 24 months postsurgery. Cost measures inflated to January 2015 values were obtained using pooled estimates from the hospital payer perspective for surgical patients.

METHODS

We employed a Markov state transition model with Monte Carlo microsimulation using a lifetime horizon to obtain an incremental cost utility ratio associated with early surgery for mild myelopathy. Parameter uncertainty was assessed through deterministic means using one-way and two-way sensitivity analyses and probabilistically using parameter estimate distributions with microsimulation (10,000 trials). Costs and utilities were discounted at 3% per annum.

RESULTS

Initial surgery for mild degenerative cervical myelopathy was associated with an incremental lifetime increase of 1.26 quality-adjusted life years (QALY) compared to observation. The associated cost incurred to the healthcare payer over a lifetime horizon was $12,894.56, resulting in a lifetime incremental cost-utility ratio of $10,250.71/QALY. Utilizing a willingness to pay threshold in keeping with the World Health Organization definition of "very cost-effective" ($54,000 CDN), the probabilistic sensitivity analysis demonstrated that 100% of cases were cost-effective.

CONCLUSIONS

Surgery compared to initial observation for mild degenerative cervical myelopathy was cost-effective from the Canadian healthcare payer perspective and was associated with lifetime gains in health-related quality of life.

Water intake and recurrent urinary tract infections prevention: economic impact analysis in seven countries

BACKGROUND

To estimate the economic impact of preventing urinary tract infections (UTI) by increasing water intake among women with recurrent UTI and low fluid intake across seven countries: France, United Kingdom, Spain, United States of America, Mexico, China and Australia.

METHODS

A Markov model was developed to compare costs and outcomes of UTIs associated with low fluid intake in women versus a strategy of primary prevention by increasing water intake. Model inputs were based on randomized controlled trial data which found that increasing water intake by 1.5 L/day decreased the risk of developing cystitis by 48% in women with low fluid intake and recurrent UTI. A time horizon of 10 years was used; outcomes were from the payer perspective and included both direct and indirect costs, reported in 2019 United States dollars ($). Discounting rates varied by country. Scenarios of increasing levels of compliance to the increased water intake strategy were evaluated.

RESULTS

The total cost of one UTI episode, including diagnostics, treatment and complications, ranged from $2164 (Mexico) to $7671 (Australia). Assuming 80% compliance with the increased water intake strategy over a 10-year time horizon, the number of UTIs prevented ranged from 435,845 (Australia) to 24150,272 (China), resulting in total savings of 286 million (Australia) to $4.4 billion (China). Across all countries, increased water intake resulted in lower cost and fewer UTIs compared with low water intake.

CONCLUSION

Preventing recurrent UTIs by increasing water intake would reduce both the clinical and economic burden associated with UTI. Public, healthcare professionals and patients should be made aware about the preventive positive impact of appropriate water intake on UTIs.

Whose Time Trade-Off Should Be Used? Anchoring Discrete Choice Experiment Latent Utilities in Health State Valuation

OBJECTIVES

To compare anchored discrete choice experiment (DCE) utility values using own versus others' time trade-off (TTO) responses in the valuation of SF-6Dv2.

METHODS

A representative sample of the general population was recruited in China. Through face-to-face interviews, both DCE and TTO data were collected from a randomly selected half of the respondents (own TTO sample), whereas only TTO data were collected from the other half (others' TTO sample). Conditional logit model was used to estimate DCE latent utilities. Three anchoring methods, including using the observed and the modeled TTO values for the worst state, and mapping DCE values onto TTO, were used to scale the latent utilities to health utilities. Prediction accuracy was assessed using intraclass correlation coefficient, mean absolute difference, and root mean squared difference compared with the mean observed TTO values between the anchoring results using the own versus others' TTO data.

RESULTS

Demographic characteristics were comparable between the own TTO sample (n = 252) and the others' TTO sample (n = 251). The mean (SD) observed TTO value for the worst state was -0.259 (0.591) for the own TTO sample and -0.236 (0.616) for the others' TTO sample. Anchoring DCE using own TTOs consistently showed a better prediction accuracy than using others' TTOs across the 3 anchoring methods in terms of the intraclass correlation coefficient (0.835-0.873 vs 0.771-0.804), mean absolute difference (0.127-0.181 vs 0.146-0.203), and root mean squared difference (0.164-0.237 vs 0.192-0.270).

CONCLUSION

When anchoring DCE-derived latent utilities onto the health utility scale, respondents' own TTO data would be preferred to TTO data obtained from a different sample.

Cost-utility Analysis Comparing Bracing Versus Observation for Skeletally Immature Patients with Thoracic Scoliosis

STUDY DESIGN

Cost-utility analysis.

OBJECTIVE

This study aimed to investigate the cost-utility of bracing versus observation in patients with thoracic scoliosis who would be indicated for bracing.

SUMMARY OF BACKGROUND DATA

There is high-quality evidence that bracing can prevent radiographic progression of spinal curvature in adolescent idiopathic scoliosis (AIS) patients with curves between 25° and 40° and Risser 0 to 2 skeletal maturity index. However, to our knowledge, the cost-utility of bracing in AIS has not been established.

METHODS

A decision-analysis model comparing bracing versus observation was developed for a hypothetical 10-year old girl (Risser 0, Sanders 3) with a 35° main thoracic curve. We estimated the probability, cost, and quality-adjusted life years (QALY) for each node based on comprehensive review of the literature. Costs were adjusted for inflation based on Consumer Price Index and reported in terms of 2020 real dollars. Incremental net monetary benefit (INMB) was calculated based on a probabilistic sensitivity analysis using Monte Carlo simulations of 1000 hypothetical patients. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates.

RESULTS

Our decision-analysis model revealed that bracing was the dominant treatment choice over observation at $50,000/QALY willingness to pay threshold. In simulation analysis of a hypothetical patient cohort, bracing was associated with lower net lifetime costs ($60,377 ± $5,340 with bracing vs. $85,279 ± $4543 with observation) and higher net lifetime QALYs (24.1 ± 2.0 with bracing vs. 23.9 ± 1.8 with observation). Bracing was associated with an INMB of $36,093 (95% confidence interval $18,894-$55,963) over observation over the patient's lifetime. The model was most sensitive to the impact of bracing versus observation on altering the probability of requiring surgery, either as an adolescent or an adult.

CONCLUSION

Cost-utility analysis supports scoliosis bracing as the preferred choice in management of appropriately indicated AIS patients with thoracic scoliosis.Level of Evidence: 5.

Association between knee symptoms, change in knee symptoms over 6-9 years, and SF-6D health state utility among middle-aged Australians

OBJECTIVES

Health state utilities (HSUs) are an input metric for estimating quality-adjusted life-years (QALY) in cost-utility analyses. Currently, there is a paucity of data on association of knee symptoms with HSUs for middle-aged populations. We aimed to describe the association of knee symptoms and change in knee symptoms with SF-6D HSUs and described the distribution of HSUs against knee symptoms' severity.

METHODS

Participants (36-49-years) were selected from the third follow-up (completed 2019) of Australian Childhood Determinants of Adult Health study. SF-6D HSUs were generated from the participant-reported SF-12. Association between participant-reported WOMAC knee symptoms' severity, change in knee symptoms over 6-9 years, and HSUs were evaluated using linear regression models.

RESULTS

For the cross-sectional analysis, 1,567 participants were included; mean age 43.5 years, female 54%, BMI ± SD 27.18 ± 5.31 kg/m². Mean ± SD HSUs for normal, moderate, and severe WOMAC scores were 0.820 ± 0.120, 0.800 ± 0.120, and 0.740 ± 0.130, respectively. A significant association was observed between worsening knee symptoms and HSUs in univariable and multivariable analyses after adjustment (age and sex). HSU decrement for normal-to-severe total-WOMAC and WOMAC-pain was - 0.080 (95% CI - 0.100 to - 0.060, p < 0.01) and - 0.067 (- 0.085 to - 0.048, p < 0.01), exceeding the mean minimal clinically important difference (0.04). Increase in knee pain over 6-9 years was associated with a significant reduction in HSU.

CONCLUSION

In a middle-aged population-based sample, there was an independent negative association between worse knee symptoms and SF-6D HSUs. Our findings may be used by decision-makers to define more realistic and conservative baseline and ongoing HSU values when assessing QALY changes associated with osteoarthritis interventions.

A Comparison of FES and SCS for Neuroplastic Recovery After SCI: Historical Perspectives and Future Directions

There is increasing evidence that neuroplastic changes can occur even years after spinal cord injury, leading to reduced disability and better health which should reduce the cost of healthcare. In motor-incomplete spinal cord injury, recovery of leg function may occur if repetitive training causes afferent input to the lumbar spinal cord. The afferent input may be due to activity-based therapy without electrical stimulation but we present evidence that it is faster with electrical stimulation. This may be spinal cord stimulation or peripheral nerve stimulation. Recovery is faster if the stimulation is phasic and that the patient is trying to use their legs during the training. All the published studies are small, so all conclusions are provisional, but it appears that patients with more disability (AIS A and B) may need to continue using stimulation and for them, an implanted stimulator is likely to be convenient. Patients with less disability (AIS C and D) may make useful recovery and improve their quality of life from a course of therapy. This might be locomotion therapy but we argue that cycling with electrical stimulation, which uses biofeedback to encourage descending drive, causes rapid recovery and might be used with little supervision at home, making it much less expensive. Such an electrical therapy followed by conventional physiotherapy might be affordable for the many people living with chronic SCI. To put this in perspective, we present some information about what treatments are funded in the UK and the US.

Continuous low-dose antibiotic prophylaxis to prevent urinary tract infection in adults who perform clean intermittent self-catheterisation: the AnTIC RCT

BACKGROUND

People carrying out clean intermittent self-catheterisation (CISC) to empty their bladder often suffer repeated urinary tract infections (UTIs). Continuous once-daily, low-dose antibiotic treatment (antibiotic prophylaxis) is commonly advised but knowledge of its effectiveness is lacking.

OBJECTIVE

To assess the benefit, harms and cost-effectiveness of antibiotic prophylaxis to prevent UTIs in people who perform CISC.

DESIGN

Parallel-group, open-label, patient-randomised 12-month trial of allocated intervention with 3-monthly follow-up. Outcome assessors were blind to allocation.

SETTING

UK NHS, with recruitment of patients from 51 sites.

PARTICIPANTS

Four hundred and four adults performing CISC and predicted to continue for ≥ 12 months who had suffered at least two UTIs in the previous year or had been hospitalised for a UTI in the previous year.

INTERVENTIONS

A central randomisation system using random block allocation set by an independent statistician allocated participants to the experimental group [once-daily oral antibiotic prophylaxis using either 50 mg of nitrofurantoin, 100 mg of trimethoprim (Kent Pharmaceuticals, Ashford, UK) or 250 mg of cefalexin (Sandoz Ltd, Holzkirchen, Germany); n = 203] or the control group of no prophylaxis (n = 201), both for 12 months.

MAIN OUTCOME MEASURES

The primary clinical outcome was relative frequency of symptomatic, antibiotic-treated UTI. Cost-effectiveness was assessed by cost per UTI avoided. The secondary measures were microbiologically proven UTI, antimicrobial resistance, health status and participants' attitudes to antibiotic use.

RESULTS

The frequency of symptomatic antibiotic-treated UTI was reduced by 48% using prophylaxis [incidence rate ratio (IRR) 0.52, 95% confidence interval (CI) 0.44 to 0.61; n = 361]. Reduction in microbiologically proven UTI was similar (IRR 0.49, 95% CI 0.39 to 0.60; n = 361). Absolute reduction in UTI episodes over 12 months was from a median (interquartile range) of 2 (1-4) in the no-prophylaxis group (n = 180) to 1 (0-2) in the prophylaxis group (n = 181). The results were unchanged by adjustment for days at risk of UTI and the presence of factors giving higher risk of UTI. Development of antimicrobial resistance was seen more frequently in pathogens isolated from urine and Escherichia coli from perianal swabs in participants allocated to antibiotic prophylaxis. The use of prophylaxis incurred an extra cost of £99 to prevent one UTI (not including costs related to increased antimicrobial resistance). The emotional and practical burden of CISC and UTI influenced well-being, but health status measured over 12 months was similar between groups and did not deteriorate significantly during UTI. Participants were generally unconcerned about using antibiotics, including the possible development of antimicrobial resistance.

LIMITATIONS

Lack of blinding may have led participants in each group to use different thresholds to trigger reporting and treatment-seeking for UTI.

CONCLUSIONS

The results of this large randomised trial, conducted in accordance with best practice, demonstrate clear benefit for antibiotic prophylaxis in terms of reducing the frequency of UTI for people carrying out CISC. Antibiotic prophylaxis use appears safe for individuals over 12 months, but the emergence of resistant urinary pathogens may prejudice longer-term management of recurrent UTI and is a public health concern. Future work includes longer-term studies of antimicrobial resistance and studies of non-antibiotic preventative strategies.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN67145101 and EudraCT 2013-002556-32.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment Vol. 22, No. 24. See the NIHR Journals Library website for further project information.

Reconsidering the minimally important difference: evidence of instability over time and across groups

BACKGROUND CONTEXT

Underlying cognitive factors have been found to influence patients' symptom experience. Current evidence suggests that concomitant changes in appraisal must be taken into account to accurately interpret change as measured by standard spine patient-reported outcomes (PROs).

PURPOSE

To investigate changes in patients' minimally important differences (MID) over recovery from spinal surgery; whether and how cognitive appraisal processes are implicated in the change trajectories.

STUDY DESIGN/SETTING

Longitudinal cohort study with up to 12 months follow-up.

PATIENT SAMPLE

Surgical patients (n = 167) with a diagnosis of disc herniation or spinal stenosis.

OUTCOME MEASURES

Standard spine patient-reported PROs were used (Rand-36, Oswestry Disability Index, Numerical Rating Scale for pain, PROMIS Pain Impact).

METHODS

This study was funded by the Feldberg Chair in Spinal Research, Sunnybrook Health Sciences Centre and the authors have no conflicts of interest. MID used an anchor technique and was computed by global assessment of change (GAC) grouping. Participants were binned into groups based on their GAC response patterns at all time points: Consistently better post-surgery, consistently worse post-surgery, and bouncers, whose GAC ratings fluctuate (ie, better-then-worse-then-better; or vice versa). Individuals' longitudinal quality of life (QOL) and appraisal slope scores were computed. QOL-appraisal slopes' correlations were computed by GAC group. Fisher's Z transformation tested the hypothesis that GAC groups differed in the QOL-appraisal relationship over time.

RESULTS

Moderate to large changes are recognized as clinically important in the early stages of recovery (ie, 6 weeks post-surgery), and over time smaller and smaller changes become important. The three pattern groups emphasized and deemphasized different standards of comparison over time, with the Better group emphasizing personal goals and the Worse and Bouncers deemphasizing doctors' input. These group differences translated to differential relationships between PRO change and appraisal changes over time.

CONCLUSIONS

The MID reflects increasingly subtle change over time in PROs. Appraisal may influence how patients experience the same (MID) change over time, with better outcomes associated with emphasizing long-term goals. PRO change seems to be driven by different standards of comparison. Potential avenues for clinical intervention are discussed.

Cost-Utility Analysis of Operative Versus Nonoperative Treatment of Thoracic Adolescent Idiopathic Scoliosis

STUDY DESIGN

Cost-utility analysis OBJECTIVE.: To compare the cost utility of operative versus nonoperative treatment of adolescent idiopathic scoliosis (AIS) and identity factors that influence cost-utility estimates.

SUMMARY OF BACKGROUND DATA

AIS affects 1% to 3% of children aged 10 to 16 years. When the major coronal curve reaches 50°, operative treatment may be considered. The cost utility of operative treatment of AIS is unknown.

METHODS

A decision-analysis model comparing operative versus nonoperative treatment was developed for a hypothetical 15-year-old skeletally mature girl with a 55° right thoracic (Lenke 1) curve. The AIS literature was reviewed to estimate the probability, health utility, and quality-adjusted life years (QALYs) for each event. For the conservative model, we assumed that operative treatment did not result directly in any QALYs gained, and the health utility in AIS patients was the same as the age-matched US population mean. Costs were inflation-adjusted at 3.22% per year to 2015 US dollars. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. Incremental cost utility ratio (ICUR) and incremental net monetary benefit were calculated. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates.

RESULTS

Operative treatment was favored in 98.5% of simulations, with a median ICUR of $20,600/QALY (95% confidence interval, $20,500-$21,900) below the societal willingness-to-pay threshold (WTPT) of $50,000/QALY. The median incremental net monetary benefit associated with operative treatment was $15,100 (95% confidence interval, $14,800-$15,700). Operative treatment produced net monetary benefit across various WTPTs. Factors that most affected the ICUR were net costs associated with uncomplicated operative treatment, undergoing surgery during adulthood, and development of pulmonary complications.

CONCLUSION

Cost-utility analysis suggests that operative treatment of AIS is favored over nonoperative treatment and falls below the $50,000/QALY WTPT for patients with Lenke 1 curves.

LEVEL OF EVIDENCE

2.

Continuous low-dose antibiotic prophylaxis for adults with repeated urinary tract infections (AnTIC): a randomised, open-label trial

BACKGROUND

Repeated symptomatic urinary tract infections (UTIs) affect 25% of people who use clean intermittent self-catheterisation (CISC) to empty their bladder. We aimed to determine the benefits, harms, and cost-effectiveness of continuous low-dose antibiotic prophylaxis for prevention of recurrent UTIs in adult users of CISC.

METHODS

In this randomised, open-label, superiority trial, we enrolled participants from 51 UK National Health Service organisations. These participants were community-dwelling (as opposed to hospital inpatient) users of CISC with recurrent UTIs. We randomly allocated participants (1:1) to receive either antibiotic prophylaxis once daily (prophylaxis group) or no prophylaxis (control group) for 12 months by use of an internet-based system with permuted blocks of variable length. Trial and laboratory staff who assessed outcomes were masked to allocation but participants were aware of their treatment group. The primary outcome was the incidence of symptomatic, antibiotic-treated UTIs over 12 months. Participants who completed at least 6 months of follow-up were assumed to provide a reliable estimate of UTI incidence and were included in the analysis of the primary outcome. Change in antimicrobial resistance of urinary and faecal bacteria was monitored as a secondary outcome. The AnTIC trial is registered at ISRCTN, number 67145101; and EudraCT, number 2013-002556-32.

FINDINGS

Between Nov 25, 2013, and Jan 29, 2016, we screened 1743 adult users of CISC for eligibility, of whom 404 (23%) participants were enrolled between Nov 26, 2013, and Jan 31, 2016. Of these 404 participants, 203 (50%) were allocated to receive prophylaxis and 201 (50%) to receive no prophylaxis. 1339 participants were excluded before randomisation. The primary analysis included 181 (89%) adults allocated to the prophylaxis group and 180 (90%) adults in the no prophylaxis (control) group. 22 participants in the prophylaxis group and 21 participants in the control group were not included in the primary analysis because they were missing follow-up data before 6 months. The incidence of symptomatic antibiotic-treated UTIs over 12 months was 1·3 cases per person-year (95% CI 1·1-1·6) in the prophylaxis group and 2·6 (2·3-2·9) in the control group, giving an incidence rate ratio of 0·52 (0·44-0·61; p<0·0001), indicating a 48% reduction in UTI frequency after treatment with prophylaxis. Use of prophylaxis was well tolerated: we recorded 22 minor adverse events in the prophylaxis group related to antibiotic prophylaxis during the study, predominantly gastrointestinal disturbance (six participants), skin rash (six participants), and candidal infection (four participants). However, resistance against the antibiotics used for UTI treatment was more frequent in urinary isolates from the prophylaxis group than in those from the control group at 9-12 months of trial participation (nitrofurantoin 12 [24%] of 51 participants from the prophylaxis group vs six [9%] of 64 participants from the control group with at least one isolate; p=0·038), trimethoprim (34 [67%] of 51 vs 21 [33%] of 64; p=0·0003), and co-trimoxazole (26 [53%] of 49 vs 15 [24%] of 62; p=0·002).

INTERPRETATION

Continuous antibiotic prophylaxis is effective in reducing UTI frequency in CISC users with recurrent UTIs, and it is well tolerated in these individuals. However, increased resistance of urinary bacteria is a concern that requires surveillance if prophylaxis is started.

FUNDING

UK National Institute for Health Research.

Quality of Life and Health Utility Scores Among Canadians Living With Traumatic Spinal Cord Injury - A National Cross-Sectional Study

STUDY DESIGN

National, multicenter, cross-sectional study.

OBJECTIVE

The goal of this study was to provide overall quality of life (QOL) and health utility (HU) values for patients with traumatic spinal cord injury (SCI) stratified by injury level and neurological status.

SUMMARY OF BACKGROUND DATA

Traumatic SCI is a leading cause of disability. Varying injury level and severity generate a spectrum of neurological dysfunction and reduction in long-term QOL.

METHODS

The Canadian SCI Community Survey was sent to Canadians living in the community after SCI. The impact of demographics, complications, and SCI classification on QOL was assessed using Analysis of variance, multiple linear regressions and ordinal logistic regression analyses.

RESULTS

There were 1109 respondents with traumatic SCI. american spinal injury association impairment scale (AIS) grade was reported to be cervical motor complete in 20%, cervical motor incomplete in 28%, thoracolumbar motor complete in 32%, thoracolumbar motor incomplete in 16%, and normal (any level) in 1%. Injury level or AIS grade had no impact on either HU or QOL. The physical component of health-related quality of life (HRQOL) was significantly affected by the neurological level, but not the social or mental components. With a mean health utility score of 0.64 ± 0.12, SCI patients living in the community reported having HRQOL similar to patients after total knee arthroplasty or lumbar spinal stenosis decompression.

CONCLUSION

QOL or HU measured by generic HRQOL outcome tools should not be used as outcomes to assess the effectiveness of interventions targeting neurological function in traumatic SCI. A disease-specific instrument that captures the nuances specific to spinal cord injury patients is required.

LEVEL OF EVIDENCE

1.

Computer-Assessed Preference-Based Quality of Life in Patients with Spinal Cord Injury

Objectives

Our aims were to (1) measure quality of life (QoL) in spinal cord injury (SCI) patients using different methods and analyze differences; (2) enable targeted treatments by identifying variables that affect QoL; and (3) provide decision-makers with useful data for cost-utility analyses in SCI population.

Methods

Seventy-one participants were enrolled. The computer-based tool UceWeb was used to elicit QoL in terms of utility coefficients, through the standard gamble, time trade-off, and rating scale methods. The SF36 questionnaire was also administered. Statistical analyses were performed to find predictors of QoL among collected variables.

Results

Median values for rating scale, time trade-off, and standard gamble were 0.60, 0.82, and 0.85, respectively. All scales were significantly correlated. Rating scale and SF36 provided similar values, significantly lower than the other methods. Impairment level, male gender, older age, living alone, and higher education were correlated with lower QoL but accounted for only 20% of the variation in utility coefficients.

Conclusions

Demographic and clinical variables are useful to predict QoL but do not completely capture utility coefficients variability. Therefore, direct preference-based utility elicitation should be strengthened. Finally, this is the first study providing data that can be used as a reference for cost-utility analyses in the Italian SCI population.

Probiotics for preventing urinary tract infection in people with neuropathic bladder

BACKGROUND

Neuropathic or neurogenic bladder describes a process of dysfunctional voiding as the result of injury in the brain, spinal cord or nerves innervating the bladder. People with neuropathic bladder, such as from spinal cord injury (SCI), are at significant risk of morbidity from urinary tract infections (UTI). Effective methods to prevent UTI in people with SCI have been sought for many years. Probiotics (micro-organisms that exert beneficial health effects in the host) have been recommended for bacterial interference of the urological tract to reduce colonisation by uropathogen and to manage the dual problems of infection and antibiotic resistance.

OBJECTIVES

This review looked at the benefits and harms of probiotics in preventing symptomatic UTI in people with neuropathic bladder compared with placebo, no therapy, or non-antibiotic prophylaxis (cranberry juice, methenamine hippurate, topical oestrogen).

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 10 March 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs), quasi-RCTs and cross-over RCTs looking at the use of probiotics for the prophylaxis of UTI in people with neuropathic bladders was considered for inclusion. Men, women and children of all ages with neuropathic bladders from neurological injury such as suprapontine, supra sacral and sacral aetiologies was included. All bladder management types, including reflex voiding, time voiding, indwelling and intermittent catheterization were eligible for this review.Studies comparing probiotics to placebo, no treatment or other non-antibiotic prophylaxis was included. Studies comparing probiotics with antibiotics or in combination with antibiotics were excluded.

DATA COLLECTION AND ANALYSIS

Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) or standardised mean difference (SMD) and 95% CI were planned for continuous outcomes.

MAIN RESULTS

This review includes a total of three studies (one cross-over and two parallel RCTs) which involved 110 participants. All three studies looked at intravesical instillation of a low virulent Escherichia coli (E. coli) strain in reducing the risk of symptomatic UTI in participants with neuropathic bladder, predominantly from SCI. Two studies used the E. coli 83972 strain and one study used the E. coli HU2117 strain.We did not find any RCTs involving other probiotics or other routes of administration for preventing UTI in people with neuropathic bladder.There was consistency in definition of symptomatic UTI in all three studies. Symptoms that all studies considered were relevant to diagnose UTI were adequately defined. All three studies defined microbiological diagnosis of symptomatic UTI.Asymptomatic bacteriuria was not considered an outcome measure in any of the included studies; however it was defined in two studies to establish successful inoculation.It is uncertain if the risk of symptomatic UTI is reduced with bladder inoculation using E. coli because the certainty of the evidence is very low (3 studies, 110 participants: RR 0.32, 95% CI 0.08 to 1.19; I2 = 82%).Two studies reported adverse events. One study reported one episode of autonomic dysreflexia. One study reported three symptomatic UTI occurring in two patients, and two studies mentioned the absence of septicaemia and pyelonephritis. Intravesical instillation was reported as "generally safe". One study reported high attrition rates in participants due to the need to adhere to strict instillation protocols.The overall quality of the studies was poor. All three studies had high risk of attrition bias due to failure of an intention-to-treat analysis which undermines the randomisation process and weakened the results of the studies. All three studies also had high risk of reporting bias.

AUTHORS' CONCLUSIONS

In this review, there were no studies identified addressing oral probiotics in preventing UTI in people with neuropathic bladder. It is uncertain if the risk of symptomatic UTI is reduced in people with neuropathic bladders via intravesical instillation of non-pathogenic E. coli as data were derived from small studies with high risk of bias.Although very minimal levels of harm was reported with this procedure, due to variable success rates, the need for strict adherence to instillation protocols together with high attrition rates in these studies, it is doubtful bladder instillation will be a widely accepted intervention in its current form.It is recommended that further appropriately powered RCTs with more robust methodological reporting be carried out.

Healthcare resource consumption for intermittent urinary catheterisation: cost-effectiveness of hydrophilic catheters and budget impact analyses

OBJECTIVES

This study presents a cost-effectiveness analysis comparing hydrophilic coated to uncoated catheters for patients performing urinary intermittent catheterisation. A national budget impact analysis is also included to evaluate the impact of intermittent catheterisation for management of bladder dysfunctions over a period of 5 years.

DESIGN

A Markov model (lifetime horizon, 1 year cycle length) was developed to project health outcomes (life years and quality-adjusted life years) and economic consequences related to patients using hydrophilic coated or uncoated catheters. The model was populated with catheter-related clinical efficacy data retrieved from randomised controlled trials and quality-of-life data (utility weights) from the literature. Cost data (EUR, 2015) were estimated on the basis of healthcare resource consumption derived from an e-survey addressed to key opinion leaders in the field.

SETTING

Italian Healthcare Service perspective.

POPULATION

Patients with spinal cord injury performing intermittent urinary catheterisation in the home setting.

MAIN OUTCOME MEASURES

Incremental cost-effectiveness and cost-utility ratios (ICER and ICUR) of hydrophilic coated versus uncoated catheters and associated healthcare budget impact.

RESULTS

The base-case ICER and ICUR associated with hydrophilic coated catheters were €20 761 and €24 405, respectively. This implies that hydrophilic coated catheters are likely to be cost-effective in comparison to uncoated ones, as proposed Italian threshold values range between €25 000 and €66 400. Considering a market share at year 5 of 89% hydrophilic catheters and 11% uncoated catheters, the additional cost for Italy is approximately €12 million in the next 5 years (current market share scenario for year 0: 80% hydrophilic catheters and 20% uncoated catheters).

CONCLUSIONS

Considered over a lifetime, hydrophilic coated catheters are potentially a cost-effective choice in comparison to uncoated ones. These findings can assist policymakers in evaluating intermittent catheterisation in patients with spinal cord injury.

Surgery for degenerative cervical myelopathy: a patient-centered quality of life and health economic evaluation

BACKGROUND CONTEXT

Degenerative cervical myelopathy (DCM) represents the most common cause of non-traumatic spinal cord impairment in adults. Surgery has been shown to improve neurologic symptoms and functional status, but it is costly. As sustainability concerns in the field of health care rise, the value of care has come to the forefront of policy decision-making. Evidence for both health-related quality of life outcomes and financial expenditures is needed to inform resource allocation decisions.

PURPOSE

This study aimed to estimate the lifetime incremental cost-utility of surgical treatment for DCM.

DESIGN/SETTING

This is a prospective observational cohort study at a Canadian tertiary care facility.

PATIENT SAMPLE

We recruited all patients undergoing surgery for DCM at a single center between 2005 and 2011 who were enrolled in either the AOSpine Cervical Spondylotic Myelopathy (CSM)-North America study or the AOSpine CSM-International study.

OUTCOME MEASURES

Health utility was measured at baseline and at 6, 12, and 24 months following surgery using the Short Form-6D (SF-6D) health utility score. Resource expenditures were calculated on an individual level, from the hospital payer perspective over the 24-month follow-up period. All costs were obtained from a micro-cost database maintained by the institutional finance department and reported in Canadian dollars, inflated to January 2015 values.

METHODS

Quality-adjusted life year (QALY) gains for the study period were determined using an area under the curve calculation with a linear interpolation estimate. Lifetime incremental cost-to-utility ratios (ICUR) for surgery were estimated using a Markov state transition model. Structural uncertainty arising from lifetime extrapolation and the single-arm cohort design of the study were accounted for by constructing two models. The first included a highly conservative assumption that individuals undergoing nonoperative management would not experience any lifetime neurologic decline. This constraint was relaxed in the second model to permit more general parameters based on the established natural history. Deterministic and probabilistic sensitivity analyses were employed to account for parameter uncertainty. All QALY gains and costs were discounted at a base of 3% per annum. Statistical significance was set at the .05 level.

RESULTS

The analysis included 171 patients; follow-up was 96.5%. Mean age was 58.2±12.0 years and baseline health utility was 0.56±0.14. Mean QALY gained over the 24-month study period was 0.139 (95% confidence interval: 0.109-0.170, p<.001) and the mean 2-year cost of treatment was $19,217.82±12,404.23. Cost associated with the operation comprised 65.7% of the total. The remainder was apportioned over presurgical preparation and postsurgical recovery. Three patients required a reoperation over the 2-year follow-up period. The costs of revision surgery represented 1.85% of the total costs. Using the conservative model structure, the estimated lifetime ICUR of surgical intervention was $20,547.84/QALY gained, with 94.7% of estimates falling within the World Health Organization definition of "very cost-effective" ($54,000 CAD). Using the more general model structure, the estimated lifetime ICUR of surgical intervention was $11,496.02/QALY gained, with 97.9% of estimates meeting the criteria to be considered "very cost-effective."

CONCLUSIONS

Surgery for DCM is associated with a significant quality of life improvement. The intervention is cost-effective and, from the perspective of the hospital payer, should be supported.

Establishment of Health Utility Indices for Post-Infectious Functional Gastrointestinal Disorders in Active Duty US Military

INTRODUCTION

Knowledge of disease burden attributable to functional gastrointestinal disorders (FGD) in travelers is lacking, despite the high incidence of travelers' diarrhea (TD) associated with increased FGD risk. One tool for assessing the impact of disease on health-related quality of life is the health utility index (HUI), which values health states based on preferential health outcomes. Health utilities can be used as preference weights in the estimation of quality-adjusted life-years (QALYs).

METHODS

Six months following travel to Egypt or Turkey, 120 US military personnel completed a survey on TD during deployment, health-related quality of life (SF-36), and the onset of functional bowel disorders (Rome II). Elements from the SF-36 were used to develop SF-6D values, which were combined with health state valuations to enable calculation of HUI scores for each subject. Mean index scores were compared across functional outcomes, specific symptoms, and demographic profiles.

RESULTS

The presence of FGD significantly reduced index scores, with irritable bowel syndrome (IBS) and dyspepsia showing the greatest impact (-0.17 and -0.19, respectively) compared with those with no FGD (p < 0.05). Importantly, however, several individuals met multiple FGD outcome definitions. Additionally, a number of symptoms associated with abnormal bowel habits and abdominal pain were associated with reduced index scores regardless of outcome.

CONCLUSION

FGD are associated with significant morbidity as assessed by HUIs. Given the strong link between TD and FGD as well as the large number of travelers from the developed to the developing world, additional study is needed to further understand this association and efforts aimed at primary disease prevention are warranted.

Right care, right time, right place: improving outcomes for people with spinal cord injury through early access to intervention and improved access to specialised care: study protocol

Background

Traumatic spinal cord injury is a devastating condition impacting adversely on the health and wellbeing, functioning and independence, social participation and quality of life of the injured person. In Australia, there are approximately 15 new cases per million population per year; economic burden estimates suggest 2 billion dollars annually. For optimal patient outcomes expert consensus recommends expeditious transfer (“<24 hours of injury”) to a specialist Spinal Cord Injury Unit, where there is an interdisciplinary team equipped to provide comprehensive care for the many and complex issues associated with traumatic spinal cord injury. No study of this patient population has been undertaken, that assessed the extent to which care received reflected clinical guidelines, or examined the patient journey and outcomes in relation to this. The aims of this study are to describe the nature and timing of events occurring before commencement of specialist care, and to quantify the association between these events and patient outcomes.

Methods and design

The proposed observational study will recruit a prospective cohort over two years, identified at participating sites across two Australian states; Victoria and New South Wales. Included participants will be aged 16 years and older and diagnosed with a traumatic spinal cord injury. Detailed data will be collected from the point of injury through acute care and subacute rehabilitation, discharge from hospital and community reintegration. Items will include date, time, location and external cause of injury; ambulance response, assessments and management; all episodes of hospital care including assessments, vital signs, diagnoses and treatment, inter-hospital transfers, surgical interventions and their timing, lengths of stay and complications. Telephone follow-up of survivors will be conducted at 6, 12 and 24 months.

Discussion

There is limited population level data on the effect of delayed commencement of specialist care (>24 hours) in a Spinal Cord Injury Unit. Examining current health service and clinical intervention pathways in this Australian population-based sample, in relation to their outcomes, will provide an understanding of factors associated with patient flow, resource utilisation and cost, and patient and family quality of life. Barriers to streamlined effective early-care pathways and facilitators of optimal treatment for these patients will be identified.

Spinal cord injury: how can we improve the classification and quantification of its severity and prognosis?

The preservation of functional neural tissue after spinal cord injury (SCI) is the basis for spontaneous neurological recovery. Some injured patients in the acute phase have more potential for recovery than others. This fact is problematic for the construction of clinical trials because enrollment of subjects with variable recovery potential makes it difficult to detect effects, requires large sample sizes, and risks Type II errors. In addition, the current methods to assess injury and recovery are non-quantitative and not sensitive. It is likely that therapeutic combinations will be necessary to cause substantially improved function after SCI, thus we need highly sensitive techniques to evaluate changes in motor, sensory, autonomic and other functions. We review several emerging neurophysiological techniques with high sensitivity. Quantitative methods to evaluate residual tissue sparing after severe acute SCI have not entered widespread clinical use. This reduces the ability to correlate structural preservation with clinical outcome following SCI resulting in enrollment of subjects with varying patterns of tissue preservation and injury into clinical trials. We propose that the inclusion of additional measures of injury severity, pattern, and individual genetic characteristics may enable stratification in clinical trials to make the testing of therapeutic interventions more effective and efficient. New imaging techniques to assess tract injury and demyelination and methods to quantify tissue injury, inflammatory markers, and neuroglial biochemical changes may improve the evaluation of injury severity, and the correlation with neurological outcome, and measure the effects of treatment more robustly than is currently possible. The ability to test such a multimodality approach will require a high degree of collaboration between clinical and research centers and government research support. When the most informative of these assessments is determined, it may be possible to identify patients with substantial recovery potential, improve selection criteria and conduct more efficient clinical trials.

Exploring psychometric properties of the SF-6D, a preference-based health-related quality of life measure, in the context of spinal cord injury

PURPOSE

The validity of the SF-6D, a preference-based measure of health-related quality of life, is not well explored in the context of spinal cord injury (SCI). The aim of this analysis was to assess appropriate measurement properties of the SF-6D in a sample of individuals living with SCI.

METHODS

Longitudinal data from the Rick Hansen Spinal Cord Injury Registry were used. Responses to the 36-item short-form health survey were transformed into SF-6D utility scores. We investigated practicality, floor and ceiling effects, and responsiveness to change. Responsiveness to change was explored using three different anchors that reflected changes in self-reported health, functional independence, and life satisfaction. Discriminative validity was assessed by ten a priori defined hypotheses, with a distinction made between 'strong' and 'weak' hypotheses.

RESULTS

Three hundred and fifty-eight individuals with SCI were included in this analysis. Practicality was deemed acceptable based on a completion rate of 94%. The SF-6D showed low responsiveness to detect important health changes over time, and differences in responsiveness were found between individuals with paraplegia and tetraplegia. All five strong hypotheses and three weak hypotheses were confirmed.

CONCLUSION

The SF-6D demonstrated good practicality and discriminative validity in this sample. The failure to detect self-reported and clinically important health changes requires further consideration. Comparative performance of the SF-6D (i.e., how the SF-6D performs against other preference-based measures) is unknown in the SCI context and requires further research.

Cost-effectiveness of supported employment for veterans with spinal cord injuries

OBJECTIVE

To estimate the cost-effectiveness of a supported employment (SE) intervention that had been previously found effective in veterans with spinal cord injuries (SCIs).

DESIGN

Cost-effectiveness analysis, using cost and quality-of-life data gathered in a trial of SE for veterans with SCI.

SETTING

SCI centers in the Veterans Health Administration.

PARTICIPANTS

Subjects (N=157) who completed a study of SE in 6 SCI centers. Subjects were randomly assigned to the intervention of SE (n=81) or treatment as usual (n=76).

INTERVENTION

A vocational rehabilitation program of SE for veterans with SCI.

MAIN OUTCOME MEASURES

Costs and quality-adjusted life years, which were estimated from the Veterans Rand 36-Item Health Survey, extrapolated to Veterans Rand 6 Dimension utilities.

RESULTS

Average cost for the SE intervention was $1821. In 1 year of follow-up, estimated total costs, including health care utilization and travel expenses, and average quality-adjusted life years were not significantly different between groups, suggesting the Spinal Cord Injury Vocational Integration Program intervention was not cost-effective compared with usual care.

CONCLUSIONS

An intensive program of SE for veterans with SCI, which is more effective in achieving competitive employment, is not cost-effective after 1 year of follow-up. Longer follow-up and a larger study sample will be necessary to determine whether SE yields benefits and is cost-effective in the long run for a population with SCI.

Trial-based clinical and economic analyses: the unhelpful quest for conformity

Where there is conformity across the findings, interpretation and implications of 'clinical’ and 'economic’ research, there is limited cause for concern. However, there is often unease when apparent contradictory conclusions are drawn from the same study. Given the ever increasing role for economic evaluation in healthcare decision making, this commentary challenges the necessity of compatibility between clinical and economic evaluation.

Exploring the consistency of the SF-6D

OBJECTIVE

The six-dimensional health state short form (SF-6D) was designed to be derived from the short-form 36 health survey (SF-36). The purpose of this research was to compare the SF-6D index values generated from the SF-36 (SF-6DSF-36) with those obtained from the SF-6D administered as an independent instrument (SF-6DInd). The goal was to assess the consistency of respondents' answers to these two methods of deriving the SF-6D.

METHODS

Data were obtained from a sample of the Portuguese population (n = 414). Agreement between the instruments was assessed on the basis of a descriptive system and their indexes. The analysis of the descriptive system was performed by using a global consistency index and an identically classified index. Agreement was also explored by using correlation coefficients. Parametric tests were used to identify differences between the indexes. Regression models were estimated to understand the relationship between them.

RESULTS

The SF-6DInd generates higher values than does the SF-6DSF-36. There were significant differences between the indexes across sociodemographic groups. There was a significant ceiling effect in the SF-6DInd but not in the SF-6DSF-36. The correlation between the indexes was high but less than what was anticipated. The global consistency index identified the dimensions with larger differences. Considerable differences were found in two dimensions, possibly as a result of different item contexts. Further research is needed to fully understand the role of the different layouts and the length of the questionnaires in the respondents' answers.

CONCLUSIONS

The results show that as the SF-6D was designed to derive utilities from the SF-36 it should be used in this way and not as an independent instrument.

Mapping the Gastrointestinal Quality of Life Index to short-form 6D utility scores

PURPOSE

The Gastrointestinal Quality of Life Index (GIQLI) is a disease-specific quality of life instrument that is commonly used in gastrointestinal disorders. However, no preference weights, which are used to calculate quality-adjusted life years for cost-effectiveness analyses, for this instrument have been assigned. Therefore, the objective of this study was to develop a mapping function to derive utility scores for the GIQLI.

METHODS

Patients undergoing elective laparoscopic cholecystectomy completed the short-form 6D (SF-6D), a preference-weighted utility measure, and the GIQLI at baseline and at 1 wk and 1 mo postoperatively. The responsiveness of the SF-6D to expected postoperative changes as well as the correlation between the SF-6D and the GIQLI was investigated. Ordinary least squares regression was performed to derive a mapping function using the baseline values, which was then validated using postoperative values. Adjusted r(2), mean absolute error, and root mean square error was used to determine model performance.

RESULTS

A total of 50 patients were included in the study (mean age 51.1 [standard deviation 16.8], 28% male). The SF-6D and GIQLI domains were responsive to expected postoperative changes, and there was high correlation between the SF-6D and four of the five GIQLI domains (excluding treatment effects). The final mapping function explained 63% of the variance in the derivation sample but had relatively high mean absolute error (0.075 and 0.067 in the 1-wk and 1-mo samples, respectively) and adjusted root mean square error (13.1% and 12.0% in the 1-wk and 1-mo samples, respectively).

CONCLUSIONS

The GIQLI can be accurately mapped to SF-6D preference weights at the group level but may be too inexact at the individual level.

Intermittent self catheterisation with hydrophilic, gel reservoir, and non-coated catheters: a systematic review and cost effectiveness analysis

OBJECTIVE

To determine the most effective and cost effective type of catheter for patients performing intermittent self catheterisation in the community.

DESIGN

Systematic review and meta-analysis. Results were incorporated into a probabilistic Markov model to compare lifetime costs and quality adjusted life years (QALYs).

DATA SOURCES

We searched Medline, Embase, and Cochrane and Cinahl databases from 2002 to 18 April 2011 to identify studies comparing hydrophilic, gel reservoir, and non-coated intermittent catheters. Earlier guidelines were used to identify papers published before 2002. To capture studies comparing clean and sterile non-coated intermittent self catheterisation, each database was searched from its date of inception to 18 April 2011.

MAIN OUTCOME MEASURES

Clinical outcomes included symptomatic urinary tract infection (UTI), bacteraemia, mortality, patient preference or comfort, and number of catheters used. The economic model included downstream complications of UTI and cost effectiveness was calculated as incremental cost per QALY gained.

RESULTS

Eight studies were included in the systematic review. Most were conducted in patients with spinal cord injuries, and most of the included patients were men. People using gel reservoir and hydrophilic catheters were significantly less likely to report one or more UTIs compared with sterile non-coated catheters (absolute effect for gel reservoir = 149 fewer per 1000 (95% confidence interval -7 to 198), P=0.04; absolute effect for hydrophilic = 153 fewer per 1000 (-8 to 268), P=0.04). However, there was no difference between hydrophilic and sterile non-coated catheters when outcomes were measured as mean monthly UTIs (mean difference = 0.01 (-0.11 to 0.09), P=0.84) or total UTIs at 1 year (mean difference = 0.18 (-0.50 to 0.86), P=0.60). There was little difference in the incidence of one or more UTIs for people using clean versus sterile non-coated catheters (absolute effect = 12 fewer per 1000 (-134 to 146), P=0.86). Although the most effective, gel reservoir catheters cost >£54,350 per QALY gained and are therefore not cost effective compared with clean non-coated self catheterisation.

CONCLUSION

The type of catheter used for intermittent self catheterisation seems to make little difference to the risk of symptomatic UTI. Given large differences in resource use, clean non-coated catheters are most cost effective. However, because of limitations and gaps in the evidence base and the designation of non-coated catheters as single use devices, we recommend a precautionary principle should be adopted and that patients should be offered a choice between hydrophilic and gel reservoir catheters.

Health-related quality of life changes associated with buprenorphine treatment for opioid dependence

BACKGROUND

Few studies have described improvement in health-related quality of life (HRQOL) associated with opioid dependence treatment with buprenorphine (ODT-B).

OBJECTIVE

To evaluate HRQOL changes in domain scores, physical and mental component summaries, and health utilities (HUs) associated with ODT-B using the Short Form 36 (SF-36).

METHODS

We assessed HRQOL changes in a substudy of a pharmacokinetic study that compared buprenorphine oral tablet and liquid dosage formulations over 16 weeks. Individuals, aged 18-65 years, were screened for opioid dependence. They were excluded if they would not agree to birth control or had a serious medical condition. Subjects received psychosocial counseling and weekly group therapy. The SF-36 was administered upon enrollment and at 4-week intervals. We used the SF-6D to estimate HUs. We performed intention to treat (ITT) analyses based on the last observation available for each subject. Paired t tests of each domain and HU, limited to remaining patients at each 4-week interval, were also conducted.

RESULTS

Of 96 subjects enrolled, cumulative dropouts over time resulted in 80, 69, 59, and 44 subjects remaining at 4, 8, 12, and 16 weeks. There were no significant differences in opioid-positive urines, dropout rates, or dosage changes between formulations. In the ITT analyses, HRQOL improvements over time were bodily pain (62.1 vs. 69.1, P = 0.017), vitality (49.8 vs. 56.5, P = 0.001), mental health (59.9 vs. 66.0, P = 0.001), social function (66.4 vs. 74.7, P = 0.001), role emotional (59.4 vs. 71.9, P = 0.003), role physical (60.9 vs. 70.6, P = 0.005), and mental component summary (41.9 vs. 45.4, P<0.001). HU scores also improved (0.674 vs. 0.715, P = 0.001). Results from paired t tests, with only concurrently enrolled patients, showed similar improvements from baseline to 4, 8, 12, or 16 weeks.

CONCLUSION

Buprenorphine, accompanied with psychosocial counseling, was associated with improved HRQOL and HUs.

Systematic review of the impact of urinary tract infections on health-related quality of life

What's known on the subject? and What does the study add? Values for equivalent health states can vary substantially depending on the measure used and method of valuation; this has a direct impact on the results of economic analyses. To date, the majority of existing economic evaluations that include UTI as a health state refer to an analysis in which the Index of Well Being was used to estimate the quality of life experienced by young women with UTIs. Currently, there are no validated methods or filters for systematically searching for the type of generic quality of life data required for decision analytic models. This study is the only systematic review of quality of life in people with UTI in the literature. Twelve studies were identified which report quality of life using a variety of generic methods; the results of these papers were summarized in a way that is useful for a health researcher seeking to populate a decision model, design a clinical study or assess the effect of UTI on quality of life relative to other conditions. One research group provided previously unpublished data from a large cohort study; these scores were mapped to EuroQol 5-Dimension values using published algorithms and probabilistic simulations. The aim of this review was to identify studies that have evaluated the impact of symptomatic urinary tract infection (UTI) and UTI-associated bacteraemia on quality of life, and to summarize these data in a way that is useful for a health researcher seeking to populate a cost-utility model, design a clinical study or assess the effect of UTIs on quality of life relative to other conditions. We conducted a systematic search of the literature using MEDLINE, EMBASE, the NHS Economic Evaluations database, Health Technology Assessment database, Health Economics Evaluations database, Cost-Effectiveness Analysis Registry and EuroQol website. Studies that reported utility values for symptomatic UTI or UTI-associated bacteraemia derived from a generic QoL measurement tool or expert opinion were included. Studies using disease-specific instruments were excluded. Twelve studies were identified that included a generic measure of health-related quality of life for patients with UTIs. These measures included: the short-form (SF)-36 and SF-12 questionnaires; the Health Utilities Index Mark 2; Quality of Well Being; the Index of Well Being, standard gamble; the Health and Activity Limitation Index; and expert opinion. The authors of studies using either of the SF questionnaires were contacted for additional data. One research group provided previously unpublished data from a large cohort study; these scores were mapped to EuroQol 5-Dimension (EQ-5D) values using published algorithms and probabilistic simulations. The present review provides health researchers with several sources from which to select utility values to populate cost-utility models. It also shows that very few studies have measured quality of life in patients with UTI using generic preference-based measures of health and none have evaluated the impact of this health state on quality of life in children. Future studies ought to consider the inclusion of commonly used preference-based measures of health, such as the EQ-5D, in all patient populations experiencing symptomatic UTI or UTI-related complications.

Modification of the SF-36 for a headache population changes patient-reported health status

BACKGROUND

Using standard quality of life and disability measures may not accurately capture these constructs in specific health populations such as headache patients. Modifying the wording of standard measures such as the Short-Form 36 (SF-36) should be considered in order to make them more applicable to specific patient populations.

OBJECTIVE

To investigate the possibility that headache patients may not consider their headaches when responding to SF-36 questions pertaining to health, physical health, pain, and bodily pain.

METHODS

The wording of several SF-36 questions were adapted for a headache population by making specific reference to "headaches" when asking people to rate the impact of health issues on their life. The results of the modified "Headache" SF-36 were compared with a similar population of transformed migraine patients who had completed the "Standard" SF-36.

RESULTS

Significant differences were found between scores for the "Standard" SF-36 group and the "Headache" SF-36 group across all SF-36 variables except for "General Health."

CONCLUSIONS

Misinterpretation of the concepts of "health,""physical health,""pain," and "bodily pain," although commonly used by the SF-36 in many populations, could influence responses on this measure, as respondents may not relate their head/headaches to these constructs. To ensure that accurate data are obtained in relation to the quality of life of headache patients, consideration should be given to using a form of the SF-36 that has been modified to allow appropriate interpretation of the questions completed by headache patients.

Comparison of distribution- and anchor-based approaches to infer changes in health-related quality of life of prostate cancer survivors

OBJECTIVE

To determine the minimal important difference (MID) in generic and prostate-specific health-related quality of life (HRQoL) using distribution- and anchor-based methods.

STUDY DESIGN AND SETTING

Prospective cohort study of 602 newly diagnosed prostate cancer patients recruited from an urban academic hospital and a Veterans Administration hospital. Participants completed generic (SF-36) and prostate-specific HRQoL surveys at baseline and at 3, 6, 12, and 24 months posttreatment. Anchor-based and distribution-based methods were used to develop MID estimates. We compared the proportion of participants returning to baseline based on MID estimates from the two methods.

RESULTS

MID estimates derived from combining distribution- and anchor-based methods for the SF-36 subscales are physical function = 7, role physical = 14, role emotional = 12, vitality = 9, mental health = 6, social function = 9, bodily pain = 9, and general health = 8; and for the prostate-specific scales are urinary function = 8, bowel function = 7, sexual function = 8, urinary bother = 9, bowel bother = 8, and sexual bother = 11. Proportions of participants returning to baseline values corresponding to MID estimates from the two methods were comparable.

CONCLUSIONS

This is the first study to assess the MID for generic and prostate-specific HRQoL using anchor-based and distribution-based methods. Although variation exists in the MID estimates derived from these two methods, the recovery patterns corresponding to these estimates were comparable.

The responsiveness of quality of life utilities to change in depression: a comparison of instruments (SF-6D, EQ-5D, and DFD)

BACKGROUND

Utilities are often a main outcome parameter in economic evaluations. Because depression has a large influence on quality of life, it is expected that utilities are responsive to changes in depression.

OBJECTIVE

To evaluate the change in utility derived from different instruments in depression, including the Short Form 6D (SF-6D), the Euroqol based on the UK (EQ-5D(UK)), the Euroqol based on the Dutch tariff (EQ-5D(NL)), and utilities derived from Beck Depression Inventory Second Edition (BDI-II) using the Depression-Free-Day method.

METHOD

This study evaluated the responsiveness, the minimally important difference, and the agreement in utility change derived from the different instruments.

RESULTS

The SF-6D, EQ-5D(UK), and EQ-5D(NL) were responsive. The minimally important difference values are in line with previous studies, about 0.3. The Depression-Free-Day method nearly always resulted in positive utility changes, even for subgroups that had no change or deterioration in health status or depression. There was poor agreement between utility changes of the SF-6D, EQ-5D (either EQ-5D(UK) or EQ-5D(NL)), and DFDu.

CONCLUSIONS

The SF-6D, EQ-5D(UK), and EQ-5D(NL) seem responsive and thus adequate for estimating utility in depression treatment. We do not recommend the use of the Depression-Fee-Day method. The low agreement between utility changes indicates that outcomes of the different instruments are incomparable.

Measuring community integration after spinal cord injury: validation of the Sydney psychosocial reintegration scale and community integration measure

OBJECTIVES

To evaluate the reliability, validity, sensitivity to change, and clinical usefulness of the Sydney Psychosocial Reintegration Scale (SPRS) and Community Integration Measure (CIM) for people with spinal cord injury (SCI).

METHODS

A sample of 58 people with recent traumatic SCI was followed up at 12 months post-discharge from inpatient rehabilitation. The SPRS, CIM, Craig Handicap Assessment and Reporting Technique (CHART) and SF-6D Health Utility Scale (SF-6D) were administered.

RESULTS

The SPRS and CIM were internally consistent (α = .80 and .78, respectively). The SPRS showed greatest sensitivity to change as measured by percentage of participants meeting minimum difference in score change over time (21%). CIM and CHART had comparable sensitivity to change (14% minimum difference). SPRS correlated significantly with CHART (r = .72, P < .001), unlike CIM. Neither SPRS nor CIM discriminated between high and low impairment, unlike CHART. Correlations with CHART and SF-6D domains supported convergent and divergent validity of the SPRS domains.

CONCLUSIONS

Research should continue to develop conceptually and psychometrically valid instruments to capture the multidimensionality of community integration. The SPRS and CIM show potential to extend measurement of community reintegration following SCI.

Quality of life instruments and definitions in individuals with spinal cord injury: a systematic review

STUDY DESIGN

A systematic review.

OBJECTIVE

To critically review quality of life (QOL) instruments used with spinal cord injury (SCI) populations.

SETTING

Vancouver, Canada.

METHODS

A systematic literature review was conducted for publications assessing the measurement properties of QOL outcome measures. Pre-established criteria were used to evaluate the measurement properties.

RESULTS

Fourteen articles reporting on 13 QOL instruments met the inclusion criteria, including the Patient Reported Impact of Spasticity Measure (PRISM), Quality of Well-being Scale, Qualiveen, Sickness Impact Profile (SIP68), Short Form (SF)-36, SF-36V, SF-12, SF-6D, Quality of Life Index, Quality of Life Profile for Adults with Physical Disabilities (QOLP-PD), Satisfaction with Life Scale, Sense of Well-being Index (SWBI), and the World Health Organization Quality of Life-BREF scale (WHOQOL-BREF). The SF-36 and WHOQOL-BREF have been widely used and validated. The SIP68, QOLP-PD, SF-36V, and SWBI are promising with limited investigation. The Qualiveen and PRISM performed well and are specific to SCI complications.

CONCLUSION

The WHOQOL-BREF is presently the most acceptable and established instrument to assess QOL after SCI. The SIP68, QOLP-PD, SF-36V, and SWBI are promising; however, require further evaluation of their measurement properties.

Health-state utilities in a prisoner population: a cross-sectional survey

BACKGROUND

Health-state utilities for prisoners have not been described.

METHODS

We used data from a 1996 cross-sectional survey of Australian prisoners (n = 734). Respondent-level SF-36 data was transformed into utility scores by both the SF-6D and Nichol's method. Socio-demographic and clinical predictors of SF-6D utility were assessed in univariate analyses and a multivariate general linear model.

RESULTS

The overall mean SF-6D utility was 0.725 (SD 0.119). When subdivided by various medical conditions, prisoner SF-6D utilities ranged from 0.620 for angina to 0.764 for those with none/mild depressive symptoms. Utilities derived by the Nichol's method were higher than SF-6D scores, often by more than 0.1. In multivariate analysis, significant independent predictors of worse utility included female gender, increasing age, increasing number of comorbidities and more severe depressive symptoms.

CONCLUSION

The utilities presented may prove useful for future economic and decision models evaluating prison-based health programs.