The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

Remediation of a historically Pb contaminated soil using a model natural Mn oxide waste

A natural Mn oxide (NMO) waste was assessed as an in situ remediation amendment for Pb contaminated sites. The viability of this was investigated using a 10 month lysimeter trial, wherein a historically Pb contaminated soil was amended with a 10% by weight model NMO. The model NMO was found to have a large Pb adsorption capacity (qmax 346 ± 14 mg g−1). However, due to the heterogeneous nature of the Pb contamination in the soils (3650.54–9299.79 mg kg−1), no treatment related difference in Pb via geochemistry could be detected. To overcome difficulties in traditional geochemical techniques due to pollutant heterogeneity we present a new method for unequivocally proving metal sorption to in situ remediation amendments. The method combines two spectroscopic techniques; namely electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). Using this we showed Pb immobilisation on NMO, which were Pb free prior to their addition to the soils. Amendment of the soil with exogenous Mn oxide had no effect on microbial functioning, nor did it perturb the composition of the dominant phyla. We conclude that NMOs show excellent potential as remediation amendments

PFI-14©: A Rasch Analysis Refinement of the Psoriasis Family Index

Objective: We aimed to assess the psychometric properties of the Psoriasis Family Index (PFI), a disease-specific instrument, to measure the secondary impact of psoriasis on the quality of life (QoL) of family members and partners of psoriasis patients. Methods: PFI data were collected from 150 accompanying family members of psoriasis patients attending the dermatology department of a secondary referral hospital. Rasch analysis was used to examine various psychometric properties of the PFI, including dimensionality, response category functioning, fit statistics, scale reliability and validity, item targeting and differential item functioning (DIF). Results: The 15-item PFI with 4 response options showed good overall fit to the Rasch model. The response category almost entirely followed the Linacre criteria, demonstrating its optimal functionality. All items except one had good fit to the Rasch model. The mean fit residual for the items was -0.085 ± 1.184 (range -1.54 to 2.7). Strict unidimensionality was achieved following removal of the misfitting item 5. The revised 14-item PFI maintained strong reliability (person separation index = 0.87). The scale showed minor mistargeting (mean difference between person and item location = 0.95 logits). None of the items displayed DIF across gender or relationship type. Conclusions: The PFI is the first disease-specific measure to quantify the QoL of family members of psoriasis patients. Following the application of Rasch analysis we now recommend the use of a 14-item version of the PFI: question No. 5 from the 15-item version has been deleted. This study demonstrates the promising psychometric performance of the PFI and confirms its potential as a useful outcome measure in future clinical research