***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background The aim of the study was to develop a menopause-specific , preference-based health-related quality -of-life ( HRQoL ) index reflecting both menopausal symptoms and potential side-effects of Hormone Replacement Therapy ( HRT ) . Methods The study had three phases : the development of a health state classification , a prospect i ve valuation survey and the estimation of a model to interpolate HRQoL indices for all remaining health states as defined by the classification . A menopausal health state classification was developed with seven dimensions : hot flushes , aching joints/muscles , anxious/frightened feelings , breast tenderness , bleeding , vaginal dryness and undesirable and rogenic signs . Each dimension contains between three and five levels and defines a total of 6,075 health states . A sample of 96 health states was selected for the valuation survey . These states were valued by a sample of 229 women aged 45 to 60 , r and omly selected from 6 general practice lists in Sheffield , UK . Respondents were asked to complete a time trade-off ( TTO ) task for nine health states , result ing in an average of 16.5 values for each health state . Results Mean health states valued range from 0.48 to 0.98 ( where 1.0 is full health and zero is for states regarded as equivalent to death ) . Symptoms , as described by the classification system , can be rank-ordered in terms of their impact ( from high to low ) on menopausal HRQoL as follows : aching joints and muscles , bleeding , breast tenderness , anxious or frightened feelings , vaginal dryness , and rogenic signs . Hot flushes did not significantly contribute to model fit . The preferred model produced a mean absolute error of 0.053 , but suffered from bias at both ends of the scale . Conclusion This article presents an attempt to directly value a condition specific health state classification . The overall fit was disappointing , but the results demonstrate that menopausal symptoms are perceived by patients to have a significant impact on utility . The overall effect is modest compared to the more generic health state descriptions such as the EQ-5D . The result ant algorithm generates a preference-based index that can be used economic evaluation and that reflects the impact of this condition To estimate patient preferences for gallstone-related treatments and outcomes , and assess how preferences vary by patient characteristics and scaling technique , the authors r and omly assigned 40 patients without gallstones to interviews based on a rating scale ( n = 22 ) and a st and ard gamble ( n = 18 ) . The patients assigned preference values ( possible values 0 to 1 ) to open cholecystectomy ( mean 0.45 by rating scale , 0.78 by st and ard gamble ) , laparoscopic cholecystectomy ( 0.71 , 0.91 ) , extracorporeal shock-wave lithotripsy ( 0.77 , 0.89 ) , acute cholecystitis ( 0.36 , 0.77 ) , lifetime biliary colic ( 0.41 , 0.71 ) , postcholecystectomy syn drome ( 0.43 , 0.79 ) , asymptomatic stone necessitating treatment with bile acids ( 0.76 , 0.96 ) , and surgical scar ( 0.79 , 0.998 ) . Preferences varied little by age , gender , or race . St and ard gamble values were highly correlated with , but significantly greater than , rating scale values . The authors conclude that  patients ' preferences for gallstone-related conditions generally are significantly less than one , and differ markedly by the scaling technique used to derive them . These results should be considered when patient preferences are incorporated into analyses of gallstone treatments . Key words : patient preference values ; rating scale ; stan dard gamble ; gallstones ; cholecystectomy ; lithotripsy . ( Med Decis Making 1994;14:307- 314 Background . Health-related quality of life can be measured by patients ' health preferences ( utilities or values ) . No method for measuring health state preferences has been st and ardized for children with arthritis or other musculoskeletal disorders ( MSKDs ) . Such a method is needed for economic evaluations of current and new pediatric treatments . Objectives . 1 ) To assess the feasibility of utility measurements in children with MSKDs , 2 ) to test the validity of the Health Utility Index ( HUI ) for these children , 3 ) to assess whether rating scale values can be mathematically converted into meaningful st and ard gamble ( SG ) utilities , and 4 ) to study whether parents can act as proxies for their children with respect to health state preferences . Methods . Eighty parents of children with MSKDs were consecutively sample d. Their children , if 8 years of age or older ( n = 55 ) , were studied concurrently . Utilities of current health states were obtained by using the SG and the HUI in r and om order . In addition , health state preferences were assessed using categorical and analog rating scales . Traditional nonutility measures of health status ( the Childhood Health Assessment Question naire [ CHAQ ] and the Activities Scale for Kids [ ASK ] ) were also completed . Intraclass correlation coefficients ( ICCs ) were calculated to assess concordance between the different utility measures and also between the ratings of the parents and their children . Results . Children 8 years of age or older were able to express the strength of their health state preferences using the HUI and rating scales . Children older than 10 years of age were able to use the SG method . The health state utilities of the parents were higher than those of their children . The utilities varied widely depending on the elicitation method . The expected high agreement between the SG and the HUI was not found ( ICC = 0.028 for parents , ICC = 0.016 for patients ) . Unlike the SG , the global utilities derived from the HUI agreed better with preferences derived from rating scales ( ICC = 0.23 - 0.25 ) and correlated with traditional health status measures ( with CHAQ , r = -0.56 ; with ASK , r = 0.46 ) both for parents and children . It was not possible to mathematically convert rating scale preferences into SG utilities . The SG utilities were unrelated to results from the rating scales , the CHAQ , and the ASK . Especially for parents , the SG utilities were very high , even when ratings of the other measures indicated poor health . Conclusions . Although it is possible to measure health utilities for children with MSKDs , the results are highly method dependent . The properties of the HUI in this population are more like those of the traditional health status measures rather than those of the SG . Preferences derived from rating scales , although easily performed , can not readily be converted into SG utilities . Parents ' ratings for their children are impaired by risk aversion This article explores various method ological issues of  patient utility  measurement in two r and omized controlled clinical trials involving 85 patients with fibromyalgia and 144 with ankylosing spondylitis . In both trials one baseline and two follow-up measurements of the patients ' preferences for their own health state and several hypothetical states were performed using the rating scale and the st and ard gamble methods .It was confirmed that st and ard gamble scores are consistently higher than rating scale scores for both the experienced and the hypothetical states . The 3-month test-retest reliability for hypothetical states measured by intraclass correlation coefficients ranged from 0.24 to 0.33 for the rating scale and from 0.43 to 0.70 for the st and ard gamble . Although the reproducibility is not high , the group mean scores are fairly stable over time . Mean st and ard gamble scores tend to differ depending on the way the measurements are undertaken . Utilities elicited with chained gambles were significantly higher than utilities elicited with basic reference gambles . At the individual level some inconsistent responses occurred . However , more than 70 % of these fell within the bounds of the measurement error , which ranged from 0.11 to 0.13 on the st and ard gamble ( 0–1 scale ) and from 8 to 10 on the rating scale ( 0–100 scale ) . The large number of negative utilities for the severe hypothetical state , which was used as an anchor point in the chained gambles , and the magnitude of these negative utilities ( down to −19 ) calls for intensified research efforts to h and le these responses in utility calculations The techniques of cost utility analysis ( CUA ) were used to evaluate the treatment of gallstone disease by open and laparoscopic cholecystectomy and by extracorporeal shockwave lithotripsy ( ESWL ) .  The application of the techniques in this context raised three method ological questions which are not satisfactorily resolved in the literature . The first is whether an ex ante or ex post perspective is best adopted for the measurement of quality of life ( QoL ) . The second is the method for converting a short term deterioration in QoL followed by full health into QALYs and the reliability of the methods available . The third is the issue of indirect costs which , in the context of a temporary disease state , can not be easily avoided . The economic evaluation found laparoscopic cholecystectomy to be generally superior than the competitor technologies ( entailing lower costs and better outcomes ) . However , the results were sensitive to assumptions about the perspective for measuring benefits and the inclusion of indirect costs Measuring preferences for schizophrenia outcomes facilitates meaningful integration of multiple outcome measures and multiple perspectives on treatment outcomes . The Time Tradeoff ( TTO ) technique , specifically developed for measuring health state preferences , is used widely in health research , but some evidence suggests that the TTO may work less well with schizophrenia than with other health conditions . This study tested the hypotheses that tailoring the time frame of the st and ard TTO to the course of schizophrenia and simplifying its presentation fromat would improve its feasibility and efficiency .  Forty clinicians provided  TTO ratings using 1 of 4 combinations of time frame and presentation format . Numeric ratings and quantitative and qualitative measures of feasibility showed that while participants preferred the simpler format , none of the alterations improved feasibility . Participants ' ratings were prone to logical inconsistencies and participants found all 4 versions of the TTO confusing and poorly suited to the context of schizophrenia treatment Objective To obtain quality -of-life ( QOL ) valuations associated with mammography screening and breast cancer treatment that are suitable for use in cost-effectiveness analyses . Methods Subjects comprised 131 women ( age range 50–79 years ) r and omly sample d from a breast cancer screening program .  In an in-person or telephone interview , women rated the QOL impact of 14 clinical scenarios ( ranging from mammography to end-of-life care for breast cancer ) using a visual analogue scale anchored by death ( 0 ) and perfect health/ quality of life ( 100 ) . Results Women rated the scenarios describing true negative results , false positive results , and routine screening mammography at 80 or above on a scale of 0–100 , suggesting that they perceive these states as being close to perfect health . They rated  adjuvant chemotherapy  ( 39.7 ; range 10–90 ) , palliation/end-of-life care ( 35.8 ; range 0–100 ) , and recurrence at 1 year ( 33.0 ; range 0–95 ) the lowest , suggesting that these health states are perceived as compromised . Women rated receiving news of a breast cancer diagnosis ( true positive ) ( 45.7 ; range 5–100 ) and receiving delayed news of a breast cancer diagnosis ( false negative ) ( 48.5 ; range 5–100 ) as being comparable to undergoing mastectomy ( 48.3 ; range 10–100 ) and radiation therapy ( 46.2 ; range 5–100 ) for breast cancer . Conclusions These data can be used to up date cost analyses of mammography screening that wish to take into account the QOL impact of screening OBJECTIVE To examine preterm , near-term , and term mothers ' self-reported quality of life in the early postpartum period . DESIGN Prospect i ve , longitudinal repeated measures design . SETTING Four medical centers in the Midwest . PATIENTS / PARTICIPANTS A convenience sample of 184 mothers of either a preterm , near-term , or term infant . MAIN OUTCOME MEASURE Maternal Postpartum Quality of Life tool . RESULTS Mothers of preterm infants scored significantly lower on the subscale psychological/baby of the Maternal Postpartum Quality of Life tool compared to mothers of near-term and term infants . CONCLUSIONS Infant gestational age at birth has relevance for maternal quality of life during the postpartum period . Health care professionals need to be cognizant relative to infant gestational age and individualize nursing care 
    Output:
    
In using adapted techniques , the primary challenge was identifying an appropriate intermediate " anchor " HS and the possibility of negative utilities .
CONCLUSIONS There is no agreement on the most method ologically robust approach to THS valuation .