Deriving preference-based single indices from non-preference based condition-specific instruments: Converting AQLQ into EQ5D indices

Suppose that one has a clinical dataset with only non-preference-based QOL data, and that one nevertheless would like to perform a cost/QALY analysis. This study reports on some efforts to establish a "mapping" relationship between AQLQ (a non-preference-based QOL instrument for asthma) and EQ5D (a preference-based generic instrument). Various methods are described in terms of associated assumptions regarding the measurement properties of the instruments. This is followed by empirical mapping, based on regressing EQ5D on AQLQ. Six main regression models and two supplementary models are identified, and the regressions carried out. Performance of each model is explored in terms of goodness of fit between observed and predicted values, and of robustness of predictions on external data. The results show that it is possible to predict mean EQ5D indices given AQLQ data. The general implications for methods of mapping non-preference-based instruments onto preference-based measures are discussed

Deriving preference-based single indices from non-preference based condition-specific instruments: converting AQLQ into EQ5D indices

Suppose that one has a clinical dataset with only non-preference-based QOL data, and that one nevertheless would like to perform a cost/QALY analysis. This study reports on some efforts to establish a “mapping” relationship between AQLQ (a non-preference-based QOL instrument for asthma) and EQ5D (a preference-based generic instrument). Various methods are described in terms of associated assumptions regarding the measurement properties of the instruments. This is followed by empirical mapping, based on regressing EQ5D on AQLQ. Six main regression models and two supplementary models are identified, and the regressions carried out. Performance of each model is explored in terms of goodness of fit between observed and predicted values, and of robustness of predictions on external data. The results show that it is possible to predict mean EQ5D indices given AQLQ data. The general implications for methods of mapping non-preference-based instruments onto preference-based measures are discussed.EQ5D; AQLQ; mapping

A study of blood contamination of Siqveland matrix bands

AIMS To use a sensitive forensic test to measure blood contamination of used Siqveland matrix bands following routine cleaning and sterilisation procedures in general dental practice. MATERIALS AND METHODS: Sixteen general dental practices in the West of Scotland participated. Details of instrument cleaning procedures were recorded for each practice. A total of 133 Siqveland matrix bands were recovered following cleaning and sterilisation and were examined for residual blood contamination by the Kastle-Meyer test, a well-recognised forensic technique. RESULTS: Ultrasonic baths were used for the cleaning of 62 (47%) bands and retainers and the remainder (53%) were hand scrubbed prior to autoclaving. Overall, 21% of the matrix bands and 19% of the retainers gave a positive Kastle-Meyer test, indicative of residual blood contamination, following cleaning and sterilisation. In relation to cleaning method, 34% of hand-scrubbed bands and 32% of hand-scrubbed retainers were positive for residual blood by the Kastle-Meyer test compared with 6% and 3% respectively of ultrasonically cleaned bands and retainers (P less than 0.001). CONCLUSIONS: If Siqveland matrix bands are re-processed in the assembled state, then adequate pre-sterilisation cleaning cannot be achieved reliably. Ultrasonic baths are significantly more effective than hand cleaning for these items of equipment

Understanding service failure and recovery: A customer-based phenomenographic approach

To date, researchers have largely considered service failure and recovery as a combination of individual constructs, often in isolation, rather than viewing failure and recovery holistically. Consequently, our understanding is fragmented. Furthermore, while some attempt has been made to gain a better understanding of service failure and recovery from both the customer and the employee’s perspective (cf. Bitner et al.1990; McColl-Kennedy and Sparks 2003), no study has employed an interpretative perspective that potentially offers a rich, in-depth approach to this important area of research. Given this gap, our paper presents the value of taking a customer-based interpretive approach to obtaining a fuller understanding of the way customers view service failure and recovery. In this paper we report the findings of our phenomenography study of twenty in-depth interviews. Not only do we argue the benefits of adopting this fresh approach to studying service failure and recovery, we also present an innovative conceptual framework derived from our phenomenographic research findings, which has significant theoretical and practical implications

Characterization of zebrafish polymerase iii promoters for the expression of short hairpin RNA interference molecules

RNA interference (RNAi) is a powerful, sequence specific, and long-lasting method of gene knockdown, and can be elicited by the expression of short-hairpin RNA (shRNA) molecules driven via polymerase III type 3 promoters from a DNA vector or transgene. To further develop RNAi as a tool in zebrafish, we have characterized the zebrafish U6 and H1 snRNA promoters and compared the efficiency of each of the promoters to express an shRNA and silence a reporter gene, relative to previously characterized U6 promoters from pufferfish, chicken, and mouse. Our results show that the zebrafish polymerase III promoters were capable of effective gene silencing in the zebrafish ZF4 cell line, but were ineffective in mammalian Vero cells. In contrast, mouse and chicken promoters were active in Vero but not ZF4 cells, highlighting the importance of homologous promoters to achieve effective silencing

Deriving preference-based single indices from non-preference based condition-specific instruments: converting AQLQ into EQ5D indices

Suppose that one has a clinical dataset with only non-preference-based QOL data, and that one nevertheless would like to perform a cost/QALY analysis. This study reports on some efforts to establish a “mapping” relationship between AQLQ (a non-preference-based QOL instrument for asthma) and EQ5D (a preference-based generic instrument). Various methods are described in terms of associated assumptions regarding the measurement properties of the instruments. This is followed by empirical mapping, based on regressing EQ5D on AQLQ. Six main regression models and two supplementary models are identified, and the regressions carried out. Performance of each model is explored in terms of goodness of fit between observed and predicted values, and of robustness of predictions on external data. The results show that it is possible to predict mean EQ5D indices given AQLQ data. The general implications for methods of mapping non-preference-based instruments onto preference-based measures are discussed

Foot related impairments and disability in juvenile idiopathic arthritis persist despite modern day treatment paradigms

Background: Foot problems such as synovitis, growth disturbance and deformity are considered common in juvenile idiopathic arthritis (JIA) and have been previously reported in over 90% of cases. The medical management of JIA appears to have improved recently however little is known about the impact of new regimes on localised joints such as in the foot. This pilot study aimed to investigate the prevalence of foot related impairments and disability, and survey the medical and podiatric management of patients in a cohort of UK children with JIA. Methods: This study was a tertiary care based cross-sectional survey. Thirty consecutive JIA patients with a history of foot and ankle arthritis completed the juvenile arthritis foot disability index questionnaire (JAFI) (0-4 for each domain), child health assessment questionnaire (CHAQ) (0-3), and pain visual analogue scale (VAS) (0-100mm). Foot deformity score (0-38), active and limited joint counts (0-77) and walking speed (m/s) were measured also recorded. Foot care provision over the previous 12 months was determined from the medical records in 23/ 30 participants. Results were analysed using simple descriptive statistics and expressed as median (range). Results: Children received biologic agents in 35%, DMARDs in 65%, and 90% of participants had received multiple intra-articular cortico-steroid injections. Median (range) values for foot disease outcomes were JAFI impairment = 1 (0-3), JAFI activity limitation = 1 (0-4) JAFI participation restriction 1 (0-3), CHAQ = 0.38 (0-2), VAS pain = 22 (0-79), foot deformity = 6 (0-20), active joints = 0 (0-7), limited joints (0-31), walking speed = 1.09 (0.84- 1.38). The JAFI scores represent mild foot related impairment and disability. Gait defects, deformity or abnormal foot posture, and/or active foot disease were the main reasons for referral. 43% of children received specialist podiatry care comprising footwear advice, orthotic therapy, and silicone digital appliances together with intrinsic muscle strengthening exercises. Conclusions: Despite DMARD/biologic regimes and specialist podiatry, foot related impairment and disability persists in JIA children. Foot care appears to be in line with current recommendations. Further study is required to determine the long-term consequences of these changes found during childhood in the foot

Deriving preference-based single indices from non-preference based condition-specific instruments: converting AQLQ into EQ5D indices

Suppose that one has a clinical dataset with only non-preference-based QOL data, and that one nevertheless would like to perform a cost/QALY analysis. This study reports on some efforts to establish a “mapping” relationship between AQLQ (a non-preference-based QOL instrument for asthma) and EQ5D (a preference-based generic instrument). Various methods are described in terms of associated assumptions regarding the measurement properties of the instruments. This is followed by empirical mapping, based on regressing EQ5D on AQLQ. Six main regression models and two supplementary models are identified, and the regressions carried out. Performance of each model is explored in terms of goodness of fit between observed and predicted values, and of robustness of predictions on external data. The results show that it is possible to predict mean EQ5D indices given AQLQ data. The general implications for methods of mapping non-preference-based instruments onto preference-based measures are discussed

DySCo: Quantitating Associations of Membrane Proteins Using Two-Color Single-Molecule Tracking

We present a general method called dynamic single-molecule colocalization for quantitating the associations of single cell surface molecules labeled with distinct autofluorescent proteins. The chief advantages of the new quantitative approach are that, in addition to stable interactions, it is capable of measuring nonconstitutive associations, such as those induced by the cytoskeleton, and it is applicable to situations where the number of molecules is small