Huiqin Yang

The use of measures of obesity in childhood for predicting obesity and the development of obesity-related diseases in adulthood: a systematic review and meta-analysis

BACKGROUND It is uncertain which simple measures of childhood obesity are best for predicting future obesity-related health problems and the persistence of obesity into adolescence and adulthood. OBJECTIVES To investigate the ability of simple measures, such as body mass index (BMI), to predict the persistence of obesity from childhood into adulthood and to predict obesity-related adult morbidities. To investigate how accurately simple measures diagnose obesity in children, and how acceptable these measures are to children, carers and health professionals. DATA SOURCES Multiple sources including MEDLINE, EMBASE and The Cochrane Library were searched from 2008 to 2013. METHODS Systematic reviews and a meta-analysis were carried out of large cohort studies on the association between childhood obesity and adult obesity; the association between childhood obesity and obesity-related morbidities in adulthood; and the diagnostic accuracy of simple childhood obesity measures. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) and a modified version of the Quality in Prognosis Studies (QUIPS) tool. A systematic review and an elicitation exercise were conducted on the acceptability of the simple measures. RESULTS Thirty-seven studies (22 cohorts) were included in the review of prediction of adult morbidities. Twenty-three studies (16 cohorts) were included in the tracking review. All studies included BMI. There were very few studies of other measures. There was a strong positive association between high childhood BMI and adult obesity [odds ratio 5.21, 95% confidence interval (CI) 4.50 to 6.02]. A positive association was found between high childhood BMI and adult coronary heart disease, diabetes and a range of cancers, but not stroke or breast cancer. The predictive accuracy of childhood BMI to predict any adult morbidity was very low, with most morbidities occurring in adults who were of healthy weight in childhood. Predictive accuracy of childhood obesity was moderate for predicting adult obesity, with a sensitivity of 30% and a specificity of 98%. Persistence of obesity from adolescence to adulthood was high. Thirty-four studies were included in the diagnostic accuracy review. Most of the studies used the least reliable reference standard (dual-energy X-ray absorptiometry); only 24% of studies were of high quality. The sensitivity of BMI for diagnosing obesity and overweight varied considerably; specificity was less variable. Pooled sensitivity of BMI was 74% (95% CI 64.2% to 81.8%) and pooled specificity was 95% (95% CI 92.2% to 96.4%). The acceptability to children and their carers of BMI or other common simple measures was generally good. LIMITATIONS Little evidence was available regarding childhood measures other than BMI. No individual-level analysis could be performed. CONCLUSIONS Childhood BMI is not a good predictor of adult obesity or adult disease; the majority of obese adults were not obese as children and most obesity-related adult morbidity occurs in adults who had a healthy childhood weight. However, obesity (as measured using BMI) was found to persist from childhood to adulthood, with most obese adolescents also being obese in adulthood. BMI was found to be reasonably good for diagnosing obesity during childhood. There is no convincing evidence suggesting that any simple measure is better than BMI for diagnosing obesity in childhood or predicting adult obesity and morbidity. Further research on obesity measures other than BMI is needed to determine which is the best tool for diagnosing childhood obesity, and new cohort studies are needed to investigate the impact of contemporary childhood obesity on adult obesity and obesity-related morbidities. STUDY REGISTRATION This study is registered as PROSPERO CRD42013005711. FUNDING The National Institute for Health Research Health Technology Assessment programme.

EOS 2D/3D X-ray Imaging System: A Systematic Review and Economic Evaluation

BACKGROUND EOS is a biplane X-ray imaging system manufactured by EOS Imaging (formerly Biospace Med, Paris, France). It uses slot-scanning technology to produce a high-quality image with less irradiation than standard imaging techniques. OBJECTIVE To determine the clinical effectiveness and cost-effectiveness of EOS two-dimensional (2D)/three-dimensional (3D) X-ray imaging system for the evaluation and monitoring of scoliosis and other relevant orthopaedic conditions. DATA SOURCES For the systematic review of EOS, electronic databases (MEDLINE, Allied and Complementary Medicine Database, BIOSIS Previews, Cumulative Index to Nursing and Allied Health Literature, The Cochrane Library, EMBASE, Health Management Information Consortium, Inspec, ISI Science Citation Index and PASCAL), clinical trials registries and the manufacturers website were searched from 1993 to November 2010. REVIEW METHODS A systematic review of studies comparing EOS with standard X-ray [film, computed radiography (CR) or digital radiography] in any orthopaedic condition was performed. A narrative synthesis was undertaken. A decision-analytic model was developed to assess the cost-effectiveness of EOS in the relevant indications compared with standard X-ray and incorporated the clinical effectiveness of EOS and the adverse effects of radiation. The model incorporated a lifetime horizon to estimate outcomes in terms of quality-adjusted life-years (QALYs) and costs from the perspective of the NHS. RESULTS Three studies met the inclusion criteria for the review. Two studies compared EOS with film X-ray and one study compared EOS with CR. The three included studies were small and of limited quality. One study used an earlier version of the technology, the Charpak system. Both studies comparing EOS with film X-ray found image quality to be comparable or better with EOS overall. Radiation dose was considerably lower with EOS: ratio of means for posteroanterior spine was 5.2 (13.1 for the study using the Charpak system); ratio of means for the lateral spine was 6.2 (15.1 for the study using the Charpak system). The study comparing EOS with CR found image quality to be comparable or better with EOS. Radiation dose was considerably lower with EOS than CR; ratio of means for the centre of the back was 5.9 and for the proximal lateral point 8.8. The lowest ratio of means was at the nape of the neck, which was 2.9. No other outcomes were assessed in the included studies, such as implications for patient management from the nature and quality of the image. Patient throughput is the major determinant of the cost-effectiveness of EOS. The average cost per procedure of EOS decreases with utilisation. Using estimates of patient throughput at national level from Hospital Episode Statistics data suggests that EOS is not cost-effective for the indications considered. Throughput in the region of 15,100 to 26,500 (corresponding to a workload of 60 to 106 patient appointments per working day) for EOS compared with a throughput of only 7530 for CR (30 patient appointments per working day) is needed to achieve an incremental cost-effectiveness ratio of £30,000 per QALY. EOS can be shown to be cost-effective only when compared with CR if the utilisation for EOS is about double the utilisation of CR. LIMITATIONS The main limitation of the systematic review of the clinical effectiveness of EOS was the limited number and quality of the data available. In particular, there were no studies assessing the potential health benefits arising from the quality and nature of the image, over and above those associated with reduced radiation exposure. Uncertainty in the model inputs was not fully explored owing to a lack of reporting of standard deviations or confidence intervals in the published literature for most of the parameters. As a result, uncertainty in the cost-effectiveness results was not presented. CONCLUSIONS Radiation dose is considerably lower with EOS than standard X-ray, whereas image quality remains comparable or better with EOS. However, the long-term health benefits from reduced radiation exposure with EOS are very small and there was a lack of data on other potential patient health benefits. The implications of any changes in the quality and nature of the EOS image compared with standard X-ray, for patient health outcomes, needs to be assessed. Given the higher cost of an EOS machine, utilisation is the major determinant of cost-effectiveness. Estimates of patient throughput at national level suggest that EOS is not cost-effective. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Systematic review of the use of bone turnover markers for monitoring the response to osteoporosis treatment: the secondary prevention of fractures, and primary prevention of fractures in high-risk groups

BACKGROUND There is currently no standard practice for the monitoring of patients receiving treatment for osteoporosis. Repeated dual-energy X-ray absorptiometry (DXA) is commonly used for monitoring treatment response, but it has its limitations. Bone turnover markers have advantages over DXA as they are non-invasive, relatively cheap and can detect changes in bone turnover rates earlier. However, they do have disadvantages, particularly high within- and between-patient variability. The ability of bone turnover markers to identify treatment non-responders and predict future fracture risk has yet to be established. OBJECTIVES We aimed to determine the clinical effectiveness, test accuracy, reliability, reproducibility and cost-effectiveness of bone turnover markers for monitoring the response to osteoporosis treatment. DATA SOURCES We searched 12 electronic databases (including MEDLINE, EMBASE, The Cochrane Library and trials registries) without language restrictions from inception to March 2012. We hand-searched three relevant journals for the 12 months prior to May 2012, and websites of five test manufacturers and the US Food and Drug Administration (FDA). Reference lists of included studies and relevant reviews were also searched. REVIEW METHODS A systematic review of test accuracy, clinical utility, reliability and reproducibility, and cost-effectiveness of two formation and two resorption bone turnover markers, in patients being treated for osteoporosis with any of bisphosphonate [alendronate (Fosamax, MSD), risedronate (Actonel, Warner Chilcott Company), zolendronate (Zometa, Novartis)], raloxifene (Evista, Eli Lilly and Company Ltd), strontium ranelate (Protelos, Servier Laboratories Ltd), denosumab (Prolia, Amgen Ltd) or teriparatide (Forsteo, Eli Lilly and Company Ltd), was undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Given the breadth of the review question, a range of study designs and outcome measures were eligible. The development of a decision model was planned to determine the cost-effectiveness of bone turnover markers for informing changes in patient management if clinical effectiveness could be established. RESULTS Forty-two studies (70 publications) met the inclusion criteria; none evaluated cost-effectiveness. Only five were randomised controlled trials (RCTs); these assessed only the impact of bone marker monitoring on aspects of adherence. No RCTs evaluated the effectiveness of bone turnover marker monitoring on treatment management. One trial suggested that feedback of a good response decreased non-persistence [hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.53 to 0.95], and feedback of a poor response increased non-persistence (HR 2.22, 95% CI 1.27 to 3.89); it is not clear whether or not the trial recruited a population representative of that seen in clinical practice. Thirty-three studies reported results of some assessment of test accuracy, mostly correlations between changes in bone turnover and bone mineral density. Only four studies reported on intra- or interpatient reliability and reproducibility in treated patients. Overall, the results were inconsistent and inconclusive, owing to considerable clinical heterogeneity across the studies and the generally small sample sizes. As clinical effectiveness of bone turnover monitoring could not be established, a decision-analytic model was not developed. CONCLUSIONS There was insufficient evidence to inform the choice of which bone turnover marker to use in routine clinical practice to monitor osteoporosis treatment response. The research priority is to identify the most promising treatment-test combinations for evaluation in subsequent, methodologically sound, RCTs. In order to determine whether or not bone turnover marker monitoring improves treatment management decisions, and ultimately impacts on patient outcomes in terms of reduced incidence of fracture, RCTs are required. Given the large number of potential patient population-treatment-test combinations, the most promising combinations would initially need to be identified in order to ensure that any RCTs focus on evaluating those strategies. As a result, the research priority is to identify these promising combinations, by either conducting small variability studies or initiating a patient registry to collect standardised data. FUNDING The National Institute for Health Research Health Technology Assessment programme.

A systematic review of the clinical effectiveness of EOS 2D/3D X-ray imaging system

PurposeTo evaluate the available evidence for the clinical effectiveness of the EOS® 2D/3D X-ray imaging system for the evaluation and monitoring of scoliosis and other relevant orthopaedic conditions.MethodsA systematic review of studies of EOS®, compared with standard X-ray film, computed radiography or digital radiography, of patients with orthopaedic conditions was undertaken. Ten electronic databases were searched. The quality of the included studies was assessed and a narrative synthesis undertaken.ResultsThree small, limited quality studies, primarily of children with scoliosis, were identified. No patient health outcomes were reported. Spinal image quality was comparable or better overall with EOS®. Radiation dose was considerably lower with EOS® than X-ray film or computed radiography; the mean entrance surface dose was over five times lower with EOS® for the posteroanterior spine radiograph and over six times lower for the lateral spine radiograph.ConclusionsThe available clinical evidence for EOS® is limited to establishing its basic technical ability. The technical advancements associated with EOS® (the ability to generate a full body scan and to construct a three-dimensional model from synchronously acquired lateral and posteroanterior images) have not been evaluated in terms of their ability to improve patient outcomes. Whilst radiation dose is a concern for orthopaedic patients who require repeated imaging, it is difficult to quantify the reductions in radiation dose seen with EOS® in terms of patient health benefits. Clinical studies that investigate the impact of EOS® on patient management are required.

Golimumab for the Treatment of Psoriatic Arthritis: A NICE Single Technology Appraisal.

The National Institute for Health and Clinical Excellence (NICE) invited the manufacturer of golimumab (Schering-Plough/Centocor) to submit evidence for the clinical and cost effectiveness of this drug for the treatment of active and progressive psoriatic arthritis (PsA) in patients who have responded inadequately to previous disease-modifying anti-rheumatic drugs (DMARDs). The Centre for Reviews and Dissemination and the Centre for Health Economics at the University of York were commissioned to act as the Evidence Review Group (ERG) to critically appraise the evidence presented by the manufacturer. This article provides a description of the company submission, the ERG review and the resulting NICE guidance. The ERG critically reviewed the evidence presented in the manufacturer’s submission and identified areas requiring clarification, for which the manufacturer provided additional evidence.The main clinical effectiveness data were derived from a single phase III randomized controlled trial (GO-REVEAL) that compared golimumab with placebo for the treatment of active and progressive patients who were symptomatic despite the use of previous DMARDs or NSAIDs. The 14-week data showed that, compared with placebo, golimumab 50 mg significantly improved joint disease response as measured by American College of Rheumatology (ACR) 20 (relative risk [RR] 5.73, 95%CI 3.24, 10.56) and Psoriatic Arthritis Response Criteria (PsARC) [RR 3.45, 95% CI 2.49, 4.87], and significantly improved skin disease response as measured by Psoriasis Area and Severity Index (PASI) 75 (RR 15.95, 95% CI 4.62, 59.11). The 24-week absolute data showed that these treatment benefits were maintained. There was a significant improvement in patients’ functional status as measured by Health Assessment Questionnaire change from baseline at 24 weeks (−0.33; p < 0.001). The open-label extension data showed that these beneficial effects were also maintained at 52 and 104 weeks. The ERG identified several issues relating to the clinical effectiveness results. Analyses of the 24-week data were less robust, failing to adjust for treatment contamination due to patient crossover at week 16. It was also unclear if these results were generalizable to clinical practice.No randomized controlled trial compared the effectiveness of different biologic therapies head-to-head. To compare the effectiveness of the biologics etanercept, infliximab, adalimumab and golimumab, the manufacturer conducted a network meta-analysis, including the comparator palliative care (usual care including use of NSAIDs or DMARDs). The ERG considered the assumption of exchangeability between the trials for the purpose of the network meta-analysis to be acceptable and the statistical approach to be reliable. The results indicated somewhat lower efficacy with golimumab than with comparator biologics.The ERG identified a number of issues relating to the cost-effectiveness results. The manufacturer calculated incremental cost-effectiveness ratios (ICERs) incorrectly by comparing golimumab with palliative care instead of the most cost-effective alternative (etanercept). Despite the manufacturer’s claim that golimumab was a cost-effective treatment option, the manufacturer’s own model showed that golimumab was unlikely to be cost effective, relative to currently accepted thresholds, when the ICERs were correctly calculated using an incremental analysis (i.e. comparing each treatment to the next best alternative). None of the sensitivity analyses carried out by the manufacturer or the ERG regarding uncertainty in the estimates of clinical effectiveness, the acquisition and administration cost of drugs, the cost of treating psoriasis and the utility functions estimated to generate health outcomes changed this conclusion.However, a key area in determining the cost effectiveness of biologics was whether they should be treated as a class. The ERG concluded that if all biologics were considered equally effective, then etanercept, adalimumab and golimumab had almost equal costs and equal QALYs, and all had an ICER of about £15 000 per QALY versus palliative care, whilst infliximab, with a higher acquisition cost, was dominated by the other biologics.The Appraisal Committee altered its position between the Appraisal Consultation Document and the Final Appraisal Determination. It ultimately recommended that golimumab be provided as an option for the treatment of active and progressive PsA in adults only if (i) it is used as described for other tumour necrosis factor inhibitor treatments in ‘Etanercept, infliximab and adalimumab for the treatment of psoriatic arthritis’ (NICE clinical guideline 199); and (ii) the manufacturer provides the 100mg dose of golimumab at the same cost as the 50mg dose.

Bevacizumab in combination with a taxane for the first-line treatment of HER2-negative metastatic breast cancer.

This paper presents a summary of the evidence review group (ERG) report into the use of bevacizumab (Avastin®, Roche) in combination with a taxane for the treatment of untreated metastatic breast cancer (mBC). The main clinical effectiveness data were derived from a single, open-label randomised controlled trial (RCT) (E2100) that evaluated the addition of bevacizumab to weekly (q.w.) paclitaxel in patients with human epidermal growth factor receptor 2-negative mBC who had not previously received chemotherapy for advanced disease. This trial reported statistically significant increases in median progression-free survival (PFS) for the addition of bevacizumab (5.8-11.3 months). Median overall survival was not significantly different between the two groups; whether this is a true null finding or due to crossover between treatment arms cannot be established, as relevant data were not collected. The manufacturer reported that the addition of bevacizumab to paclitaxel q.w. therapy was associated with a significant improvement in quality of life, as measured by FACT-B (functional assessment of cancer therapy for breast cancer) scores. However, the ERG noted that these results were based on extreme imputed values, the removal of which led to non-significant differences in quality of life. The manufacturer conducted an indirect comparison. However, owing to methodological limitations and concerns about the validity and exchangeability of the included trials, the ERG did not consider the findings to be reliable. One additional relevant RCT [AVADO (Avastin and Docetaxel); BO17708] evaluating the addition of bevacizumab to docetaxel was excluded from the manufacturers submission. This was summarised by the ERG. In terms of response rate and PFS, AVADO reported a markedly smaller benefit of adding bevacizumab to docetaxel than that reported for adding bevacizumab to q.w. paclitaxel in E2100. AVADO also reported no statistically significant effect of combination therapy versus docetaxel in terms of overall survival. The manufacturer developed a de novo economic model that considered patients with the same baseline characteristics as women in the E2100 trial. The model assessed BEV + PAC - bevacizumab 10 mg/kg every 2 weeks in combination with paclitaxel 90 mg/m2 weekly for 3 weeks followed by 1 week of rest; PAC q.w. - paclitaxel (monotherapy) 90 mg/m2 weekly for 3 weeks followed by 1 week of rest; DOC - docetaxel (monotherapy) 75 mg/m2 on day 1 every 21 days (considered current UK NHS clinical practice in the submission); and GEM + PAC - gemcitabine 1250 mg/m2 on days 1 and 8 plus paclitaxel 175 mg/m2 on day 1 every 21 days. Pairwise comparisons were made between BEV + PAC and PAC (using the E2100 trial), BEV + PAC and DOC, and BEV + PAC and GEM + PAC. Based on NHS list prices, the manufacturers model estimated incremental cost-effectiveness ratios (ICERs) for BEV + PAC of £ 117,803, £ 115,059 and £ 105,777 per QALY gained, relative to PAC, DOC and GEM + PAC regimens, respectively. If the NHS Purchasing and Supply Agency prices for PAC with a 10-g cap on the cost per patient of BEV were used instead, the ICERs for BEV + PAC were estimated at £ 77,314, £ 57,753 and £ 60,101 per QALY, respectively. The submission suggested that the regimen of BEV + DOC is not cost-effective because it is considered less effective and more costly than BEV + PAC. Analysis by the ERG suggested that alternative assumptions can increase the ICERs further and, based on current prices, no plausible changes to the model assumptions will bring the ICERs for BEV + PAC lower.

The EOS 2D/3D X-ray imaging system: a cost-effectiveness analysis quantifying the health benefits from reduced radiation exposure.

OBJECTIVES To evaluate the cost-effectiveness of the EOS(®) 2D/3D X-ray imaging system compared with standard X-ray for the diagnosis and monitoring of orthopaedic conditions. MATERIALS AND METHODS A decision analytic model was developed to quantify the long-term costs and health outcomes, expressed as quality-adjusted life years (QALYs) from the UK health service perspective. Input parameters were obtained from medical literature, previously developed cancer models and expert advice. Threshold analysis was used to quantify the additional health benefits required, over and above those associated with radiation-induced cancers, for EOS(®) to be considered cost-effective. RESULTS Standard X-ray is associated with a maximum health loss of 0.001 QALYs, approximately 0.4 of a day in full health, while the loss with EOS(®) is a maximum of 0.00015 QALYs, or 0.05 of a day in full health. On a per patient basis, EOS(®) is more expensive than standard X-ray by between £10.66 and £224.74 depending on the assumptions employed. The results suggest that EOS(®) is not cost-effective for any indication. Health benefits over and above those obtained from lower radiation would need to double for EOS to be considered cost-effective. CONCLUSION No evidence currently exists on whether there are health benefits associated with imaging improvements from the use of EOS(®). The health benefits from radiation dose reductions are very small. Unless EOS(®) can generate additional health benefits as a consequence of the nature and quality of the image, comparative patient throughput with X-ray will be the major determinant of cost-effectiveness.

Modelling the cost-effectiveness of biologic treatments for psoriatic arthritis

OBJECTIVES A probabilistic model was developed to determine the cost-effectiveness of three biologics, etanercept, infliximab and adalimumab, compared with palliative care for the treatment of active and progressive PsA in patients who have an inadequate response to standard treatment (including DMARDs). METHODS A previous model was revised to evaluate the impact of biologics on both skin and joint disease and to include new evidence from the clinical review and evidence synthesis. Initial response to biologics was determined using the PsA response criteria. The impact of biologics on the arthritis component of the disease is then modelled via a change in the HAQ and the impact of the psoriasis component measured using the Psoriasis Area and Severity Index. RESULTS For PsA patients with mild to moderate skin disease, the incremental cost-effectiveness ratio (ICER) for etanercept vs palliative care is around £18 000, and the ICER for infliximab vs etanercept is around £44 000 per quality-adjusted life year (QALY). Adalimumab is extendedly dominated. The probability that etanercept is cost effective is 0.436 at a threshold of £20 000 per QALY. Etanercept is also likely to be cost effective for patients with moderate to severe psoriasis or negligible skin involvement. CONCLUSIONS Further investigation is required to reduce uncertainties around a number of model parameters, in particular the length of time over which biologics are assumed to be effective and the progression of HAQ on and off treatment.

Identifying and enhancing risk thresholds in the detection of elder financial abuse: a signal detection analysis of professionals’ decision making

BackgroundFinancial abuse of elders is an under acknowledged problem and professionals’ judgements contribute to both the prevalence of abuse and the ability to prevent and intervene. In the absence of a definitive “gold standard” for the judgement, it is desirable to try and bring novice professionals’ judgemental risk thresholds to the level of competent professionals as quickly and effectively as possible. This study aimed to test if a training intervention was able to bring novices’ risk thresholds for financial abuse in line with expert opinion.MethodsA signal detection analysis, within a randomised controlled trial of an educational intervention, was undertaken to examine the effect on the ability of novices to efficiently detect financial abuse. Novices (n = 154) and experts (n = 33) judged “certainty of risk” across 43 scenarios; whether a scenario constituted a case of financial abuse or not was a function of expert opinion.Novices (n = 154) were randomised to receive either an on-line educational intervention to improve financial abuse detection (n = 78) or a control group (no on-line educational intervention, n = 76). Both groups examined 28 scenarios of abuse (11 “signal” scenarios of risk and 17 “noise” scenarios of no risk). After the intervention group had received the on-line training, both groups then examined 15 further scenarios (5 “signal” and 10 “noise” scenarios).ResultsExperts were more certain than the novices, pre (Mean 70.61 vs. 58.04) and post intervention (Mean 70.84 vs. 63.04); and more consistent. The intervention group (mean 64.64) were more certain of abuse post-intervention than the control group (mean 61.41, p = 0.02). Signal detection analysis of sensitivity (A´) and bias (C) revealed that this was due to the intervention shifting the novices’ tendency towards saying “at risk” (C post intervention -.34) and away from their pre intervention levels of bias (C-.12). Receiver operating curves revealed more efficient judgments in the intervention group.ConclusionAn educational intervention can improve judgements of financial abuse amongst novice professionals.

Alternative Lens Model Equations for Dichotomous Judgments about Dichotomous Criteria

Objective The Brunswik lens model typically represents a judges accuracy using parameters derived from linear regression. This is not optimal if the judgment or the ecological criterion is dichotomous. Alternative approaches, modeling dichotomies using logistic regression, or linearizing judgments with confidence ratings, have not been compared with the same data. Method Four techniques for deriving lens model equation parameters were compared: 1) linear and 2) logistic regression applied to dichotomous patient outcomes and judgments; 3) linear regression with confidence-adjusted judgments but dichotomous patient outcomes; and 4) a hybrid with a linear model of the confidence-adjusted judgments and a logistic model of the patient outcomes. Results Judgment accuracy (ra) was slightly higher with confidence adjustment of the categorical judgments. The logistic lens model accounted for a higher proportion of ra than the linear lens model; the confident-linear and hybrid lens models were intermediate. For up to a quarter of participants, different methods identified different cues as most important. Display condition differences in achievement ra and in lens model components are similar with all lens model methods. Conclusion Each of the three alternative lens model equation methods improves on the linear lens model equations decomposition of the accuracy of dichotomous judgments. Confidence adjustment improves achievement although it requires additional work from the subjects. The logistic lens model equation explains the highest proportion of achievement, but with a small stimulus set it is more vulnerable to cue intercorrelations than either the linear or the confident linear lens model equation.