Why does the Engel method work? Food demand, economies of size and household survey methods

Estimates of household size economies are needed for the analysis of poverty and inequality. This paper shows that Engel estimates of size economies are large when household expenditures are obtained by respondent recall but small when expenditures are obtained by daily recording in diaries. Expenditure estimates from recall surveys appear to have measurement errors correlated with household size. As well as demonstrating the fragility of Engel estimates of size economies, these results help resolve a puzzle raised by Deaton and Paxson (1998) about differences between rich and poor countries in the effect of household size on food demand

Serum Creatinine and Tacrolimus Assessment With VAMS Finger-Prick Microsampling: A Diagnostic Test Study

Rationale & Objective: Kidney transplant recipients require frequent venipunctures. Microsampling methods that use a finger-prick draw of capillary blood, like volumetric absorptive microsamplers (VAMS), have the potential to reduce the pain, inconvenience, and volume of blood loss associated with venipuncture. This study aimed to provide diagnostic accuracy using VAMS for measurement of tacrolimus and creatinine compared to gold standard venous blood in adult kidney transplant recipients. Study Design: Diagnostic test study. Prospective blood samples for measurement of tacrolimus and creatinine were collected using Mitra VAMS and venipuncture immediately before and 2 hours after tacrolimus dosing. Setting & Participants: A convenience sample of 40 adult kidney transplant participants in the outpatient setting. Tests Compared: Method comparison was assessed by Passing-Bablok regression and Bland-Altman analysis. The predictive performance of VAMS measurement compared to venipuncture was also assessed through estimation of the median prediction error and median absolute percentage prediction error. Results: A total of 74 tacrolimus samples and 70 creatinine samples were analyzed from 40 participants. Passing-Bablok regression showed a systematic difference between VAMS and venipuncture when measuring tacrolimus and creatinine with a slope of 1.08 (95% CI, 1.03-1.13) and a slope of 0.65 (95% CI, 0.6-0.7), respectively. These values were then corrected for the systematic difference. When used for Bland-Altman analysis, corrected values of tacrolimus and creatinine showed a bias of -0.1 μg/L and 0.04 mg/dL, respectively. Tacrolimus (corrected) and creatinine (corrected) microsampling values when compared to corresponding venipuncture values met median prediction error and median absolute percentage prediction error predefined acceptability limits of <15%. Limitations: This study was conducted in a controlled environment using a trained nurse to collect VAMS samples. Conclusions: In this study, VAMS was used to reliably measured tacrolimus and creatinine. This represents a clear opportunity for more frequent and less invasive sampling for patients

Health professionals, their medical interventions and uncertainty : a study focusing on women at midlife

Health professionals face a tension between focusing on the individual and attending to health issues for the population as a whole. This tension is intrinsic to medicine and gives rise to medical uncertainty, which here is explored through accounts of three medical interventions focused on women at midlife: breast screening, hormone replacement therapy and bone densitometry. The accounts come from interviews with UK health professionals using these medical interventions in their daily work. Drawing on the analysis of Fox [(2002). Health and Healing: The public/private divide (pp. 236–253). London: Routledge] we distinguish three aspects of medical uncertainty and explore each one of them in relation to one of the interventions. First is uncertainty about the balance between the individual and distributive ethic of medicine, explored in relation to breast screening. Second is the dilemma faced by health professionals when using medicial evidence generated through studies of populations and applying this to individuals. We explore this dilemma for hormone replacement therapy. Thirdly there is uncertainty because of the lack of a conceptual framework for understanding how new micro knowledge, such as human genetic information, can be combined with knowledge of other biological and social dimensions of health. The accounts from the bone denistometry clinic indicate the beginnings of an understanding of the need for such a framework, which would acknowledge complexity, recognising that factors from many different levels of analysis, from heredity through to social factors, interact with each other and influence the individual and their health. However, our analysis suggests biomedicine continues to be dominated by an individualised, context free, concept of health and health risk with individuals alone responsible for their own health and for the health of the population. This may continue to dominate how we perceive responsibilities for health until we establish a conceptual framework that recognises the complex interaction of many factors at macro and micro level affecting health

SIC-8000 versus hetastarch as a submucosal injection fluid for endoscopic mucosal resection: a randomized controlled trial

Background and Aims Viscous solutions provide a superior submucosal cushion for endoscopic mucosal resection (EMR). SIC-8000 (Eleview, Aries Pharmaceuticals, La Jolla, Calif) is a commercially available FDA approved solution but hetastarch is also advocated. We performed a randomized trial comparing SIC-8000 to hetastarch as submucosal injection agents for colorectal EMR. Methods This was a single-center double-blinded randomized controlled trial performed at a tertiary referral center. Patients were referred to our center with flat or sessile lesions measuring ≥15 mm in size. The primary outcome measures were the Sydney Resection Quotient (SRQ) and the rate of en bloc resections. Secondary outcomes were total volume needed for a sufficient lift, number of resected pieces, and adverse events. Results There were 158 patients with 159 adenomas (84 SIC-8000 and 75 hetastarch) and 57 serrated lesions (30 SIC-8000 and 27 hetastarch). SRQ was significantly better in the SIC-8000 group compared with hetastarch group (9.3 vs 8.1, p=0.001). There was no difference in the proportion of lesions with en bloc resections. The total volume of injectate was significantly lower with SIC-8000 (14.8 mL vs 20.6 mL, p=0.038) Conclusions SIC-8000 is superior to hetastarch for use during EMR in terms of SRQ and total volume needed, although the absolute differences were small

Home visits by family physicians during the end-of-life: Does patient income or residence play a role?

BACKGROUND: With a growing trend for those with advanced cancer to die at home, there is a corresponding increase in need for primary medical care in that setting. Yet those with lower incomes and in rural regions are often challenged to have their health care needs met. This study examined the association between patient income and residence and the receipt of Family Physician (FP) home visits during the end-of-life among patients with cancer. METHODS: Data Sources/Study Setting. Secondary analysis of linked population-based data. Information pertaining to all patients who died due to lung, colorectal, breast or prostate cancer between 1992 and 1997 (N = 7,212) in the Canadian province of Nova Scotia (NS) was extracted from three administrative health databases and from Statistics Canada census records. Study Design. An ecological measure of income ('neighbourhood' median household income) was developed using census information. Multivariate logistic regression was then used to assess the association of income with the receipt of at least one home visit from a FP among all subjects and by region of residency during the end-of-life. Covariates in the initial multivariate model included patient demographics and alternative health services information such as total days spent as a hospital inpatient. Data Extraction Methods. Encrypted patient health card numbers were used to link all administrative health databases whereas the postal code was the link to Statistics Canada census information. RESULTS: Over 45% of all subjects received at least one home visit (n = 3265). Compared to those from low income areas, the log odds of receiving at least one home visit was significantly greater among subjects who reside in middle to high income neighbourhoods (for the highest income quintile, adjusted odds ratio [OR] = 1.37, 95% confidence interval [CI] = 1.15, 1.64; for upper-middle income, adjusted OR = 1.19, 95%CI = 1.02, 1.39; for middle income, adjusted OR = 1.33, 95%CI = 1.15, 1.54). This association was found to be primarily associated with residency outside of the largest metropolitan region of the province. CONCLUSION: The likelihood of receiving a FP home visit during the end-of-life is associated with neighbourhood income particularly among patients living outside of a major metropolitan region

Comparison of the influence of cyclosporine and tacrolimus on the pharmacokinetics of prednisolone in adult male kidney transplant recipients

Cyclosporine has been observed to precipitate cushingoid features in kidney transplant recipients already on prednisolone. Some pharmacokinetic studies have demonstrated increased prednisolone exposure in patients on cyclosporine therapy compared with azathioprine, whereas other studies have found no difference. The objective of this study was to determine whether cyclosporine impacts on prednisolone exposure as compared with tacrolimus

Impact of a ring fitted cap on insertion time and adenoma detection: a randomized controlled trial

Background and Aims: Devices for flattening colon folds can improve polyp detection at colonoscopy. However, there are few data on the endoscopic ring fitted cap (EndoRings, EndoAid, Caesarea, Israel). We sought to compare adenoma detection with EndoRings with that of standard high-definition colonoscopy. Methods: A single-center randomized controlled trial of 562 patients (284 randomized to EndoRings and 278 to standard colonoscopy) at 2 outpatient endoscopy units in the Indiana University Hospital system. Adenoma detection was the primary outcome measured as adenoma detection rate (ADR) and adenomas per colonoscopy (APC). We also compared sessile serrated polyp detection rate (SSPDR), insertion times, withdrawal times, and ease of passage through the sigmoid colon. Results: EndoRings was superior to standard colonoscopy in terms of APC (1.46 vs 1.06, p=0.025) but there were no statistically significant differences in ADR or SSPDR. Mean withdrawal time (in patients with no polyps) was shorter and insertion time (all patients) was longer in the EndoRings arm by 1.8 minutes and 0.75 minutes, respectively. One provider had significantly higher detection with EndoRings and contributed substantially to the overall results. Conclusions: EndoRings can increase adenoma detection without significant increase in procedure time, but the effect varies between operators. EndoRings slows colonoscope insertion

A comparison of 2 distal attachment mucosal exposure devices: a noninferiority randomized controlled trial

Background and Aims Endocuff and Endocuff Vision are effective mucosal exposure devices for improving polyp detection during colonoscopy. AmplifEYE is a knock-off device that appears similar to the Endocuff devices but has received minimal clinical testing. Methods We performed a randomized controlled clinical trial using a noninferiority design to compare Endocuff Vision with AmplifEYE. Results The primary endpoint of adenomas per colonoscopy was similar in AmplifEYE at 1.63 (2.83) versus 1.51 (2.29) with Endocuff Vision; p=0.535. The 95% lower confidence limit was 0.88 for ratio of means, establishing noninferiority of AmplifEYE (p=0.008). There was no difference between the arms in mean insertion time, and mean inspection time (withdrawal time minus polypectomy time and time for washing and suctioning) was shorter with AmplifEYE (6.8 minutes vs 6.9 minutes, p=0.042). Conclusions AmplifEYE is noninferior to Endocuff Vision for adenoma detection. The decision of which device to use can be based on cost. Additional comparisons of AmplifEYE to Endocuff by other investigators are warranted

Endovaginal magnetic resonance imaging of stage 1A/1B cervical cancer with A T2- and diffusion-weighted magnetic resonance technique: effect of lesion size and previous cone biopsy on tumor detectability.

Objective To evaluate the effects of previous cone biopsy and lesion size on detectability of stage 1a/1b cervical cancer using endovaginal T2- and diffusion-weighted magnetic resonance imaging.Methods One hundred and thirteen patients with cervical tumor were imaged using an endovaginal coil with T2-weighted (T2-W) and diffusion-weighted single-shot echo-planar sequences; 85 managed surgically (58 with prior cone biopsy/LLETZ) were evaluated. T2-W images and ADC maps viewed simultaneously were scored positive or negative for tumor and compared with histology at surgery. MRI tumor volumes, maximum radiological and histological dimensions were recorded. ROC analysis determined the MRI volume with optimal sensitivity/specificity for identifying tumor in those without and with prior cone biopsy/LLETZ and the maximum histological dimension for correctly identifying tumor with MRI. Mean apparent diffusion coefficients (ADCs) from tumor and adjacent normal epithelium were compared.Results Sensitivity and specificity for detecting tumor in those without (100%; 100% respectively) and with (80%; 78.9% respectively) prior cone biopsy/LLETZ were significantly different (p<0.001). Following cone biopsy/LLETZ, MRI tumor volume of 83 mm3 detected tumor with 80% sensitivity, 94.7% specificity; a 5.3mm maximal histological dimension was detected on MRI with 100% sensitivity, 100% specificity. Tumor ADCs were significantly lower (p<0.001) than paired normal epithelial tissue (median, 988×10(-6) mm2/s vs. 1564×10(-6) mm2/s) but neither tumor nor epithelial ADCs differed significantly between patients with or without prior cone biopsy/LLETZ (p=0.48 and 0.15, respectively).Conclusions Endovaginal MRI with T2- and diffusion-weighted sequences has significantly lower sensitivity and specificity for tumor detection following cone biopsy/LLETZ