Dedan Opondo

A nephrolithometric nomogram to predict treatment success of percutaneous nephrolithotomy.

PURPOSE Imaging is routinely done preoperatively and postoperatively to assess patients treated with percutaneous nephrolithotomy. We developed a nomogram for percutaneous nephrolithotomy success. MATERIALS AND METHODS From November 2007 to December 2009 the CROES (Clinical Research Office of the Endourological Society) collected data on consecutive patients at 96 centers globally. Patients were evaluated for stone-free status using plain x-ray of the kidneys, ureters and bladder. Treatment success was defined as no visible stones or residual fragments less than 4 mm. Multivariate regression was used to model the relationship between preoperative descriptors and the stone-free rate. Variables included case load, prior treatment, body mass index, staghorn stones, renal anomalies, and stone burden, location and count. Bootstrapping techniques were used to validate the model. Adjusted chi-square statistic values were used to rank the prognostic value of variables. A nomogram was developed using significant predictors from the model. We assessed the predictive accuracy of the nomogram using the ROC curve AUC. The nomogram was calibrated. RESULTS Stone burden was the best predictor of the stone-free rate (chi-square = 30.27, p <0.001). Other factors associated with the stone-free rate were case volume (chi-square = 35.75, p <0.001), prior stone treatment (chi-square = 14.55, p <0.012), staghorn stone (adjusted chi-square = 4.73, p <0.029), stone location (chi-square = 14.74, p <0.001) and stone count (chi-square = 4.78, p <0.004). A nephrolithometric nomogram was developed with predictive accuracy (AUC 0.76). CONCLUSIONS The percutaneous nephrolithotomy stone-free rate can be predicted using preclinical data and radiological information. We present a nephrolithometric nomogram for percutaneous nephrolithotomy.

Impact of Case Volumes on the Outcomes of Percutaneous Nephrolithotomy

BACKGROUND Previous studies have demonstrated relationships between case volumes and outcomes in surgery. Little is known about the impact of case volumes on the outcomes of percutaneous nephrolithotomy (PCNL). OBJECTIVE To investigate the influence of case volumes on the efficacy and safety outcomes of PCNL. DESIGN, SETTING, AND PARTICIPANTS From November 2007 to December 2009, prospective data were collected by the Clinical Research Office of the Endourological Society from consecutive patients over a 1-yr period in 96 centers globally. Data of 3933 patients in the Global PCNL study database were included in this study. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Patients were divided into low- and high-volume groups based on the median annual case volume of their respective treatment center. Preoperative characteristics and outcomes were compared between the two groups. Case volume was treated as a continuous variable. The relationship between case volume and stone-free (SF) rate, complication rate, and duration of hospital stay was explored using multivariate regression analysis. RESULTS AND LIMITATIONS SF rates were higher in high-volume centers (82.5% vs 75.1%; p value <0.001). Complication rates were lower in high-volume centers (15.9% vs 21.7%; p value 0.002), whereas the mean (standard deviation [SD]) duration of stay was shorter in high-volume centers (3.4 [2.6] vs 4.9 [3.7] d; p value <0.001). SF rate increased with case volume, whereas complication rate and duration of stay diminished with increasing case volumes after adjusting for stone burden, urine culture status, American Society of Anesthesiologists score, and the presence of staghorn stones. The highest SF rates were observed in centers with >120 cases per year. CONCLUSIONS Centers that perform high numbers of PCNLs per year achieve better results. Both the efficacy and safety outcomes of PCNL improve with the number of surgeries performed in a given center per year.

LERM (Logical Elements Rule Method): A method for assessing and formalizing clinical rules for decision support

PURPOSE The aim of this study was to create a step-by-step method for transforming clinical rules for use in decision support, and to validate this method for usability and reliability. METHODS A sample set of clinical rules was identified from the relevant literature. Using an iterative approach with a focus group of mixed clinical and informatics experts, a method was developed for assessing and formalizing clinical rules. Two assessors then independently applied the method to a separate validation set of rules. Usability was assessed in terms of the time required and the error rate, and reliability was assessed by comparing the results of the two assessors. RESULTS The resulting method, called the Logical Elements Rule Method, consists of 7 steps: (1) restate the rule proactively; (2) restate the rule as a logical statement (preserving key phrases); (3) assess for conflict between rules; (4) identify concepts which are not needed; (5) classify concepts as crisp or fuzzy, find crisp definitions corresponding to fuzzy concepts, and extract data elements from crisp concepts; (6) identify rules which are related by sharing patients, actions, etc.; (7) determine availability of data in local systems. Validation showed that the method was usable with rules from various sources and clinical conditions, and reliable between users provided that the users agree on a terminology and agree on when the rule will be evaluated. CONCLUSIONS A method is presented to assist in assessing clinical rules for their amenability to decision support, and formalizing the rules for implementation. Validation shows that the method is usable and reliable between users. Use of a terminology increases reliability but also the error rate. The method is useful for future developers of systems which offer decision support based on clinical rules.

Age and Gender Related Differences in Renal Cell Carcinoma in a European Cohort

PURPOSE We evaluated the influence of age on gender related differences in the renal cell carcinoma presentation of patients operated on between 1995 and 2005 in a European country. We also assessed the trend of missing pathological data. MATERIALS AND METHODS Data on all patients who underwent radical or partial nephrectomy for renal cell carcinoma during 1995 to 2005 in The Netherlands were retrospectively collected from the prospective PALGA (Pathological Anatomical National Automated Archive) database. Patients were divided into 5 cohorts based on age at surgery, including 40 or less, 41 to 50, 51 to 60, 61 to 70 and greater than 70 years. Variables evaluated were gender differences by age, and tumor size, subtype, stage and Fuhrman grade. RESULTS A higher mean age in women was only observed in those older than 70 years (p <0.001). The male-to-female ratio was 2:1 at ages 41 to 60 years and 1.2:1 at greater than 70 years. Compared to men women had smaller tumors at ages 51 to 60 years (p = 0.03), stage pT3 was less common at age 41 years or greater (p = 0.02), and grade 2 was less common at age 61 years or greater (p <0.001). The incidence of tumors with missing data on stage (14.9%), subtype (52.2%) and grade (47.1%) decreased substantially during the study period (p <0.001). CONCLUSIONS Older age in women than in men who present to surgery for RCC was only prevalent in those older than 70 years. The male-to-female ratio was almost equal in patients older than 70 years compared to a 2:1 ratio at ages 41 to 60 years. Women presented with fewer pT3 tumors than men at age 41 years or greater. Missing pathological data decreased significantly between 1995 and 2005.

The 1-year decline in estimated glomerular filtration rate (eGFR) after radical nephrectomy in patients with renal masses and matched living kidney donors is the same

To determine short‐term differences in renal function evolution between patients with renal cell carcinoma (RCC) submitted to radical nephrectomy (RN) and living kidney donors matched for age and gender. To assess the role of co‐morbidity as a risk factor for developing an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2.

Quality of Co-Prescribing NSAID and Gastroprotective Medications for Elders in The Netherlands and Its Association with the Electronic Medical Record.

Objective To assess guideline adherence of co-prescribing NSAID and gastroprotective medications for elders in general practice over time, and investigate its potential association with the electronic medical record (EMR) system brand used. Methods We included patients 65 years and older who received NSAIDs between 2005 and 2010. Prescription data were extracted from EMR systems of GP practices participating in the Dutch NIVEL Primary Care Database. We calculated the proportion of NSAID prescriptions with co-prescription of gastroprotective medication for each GP practice at intervals of three months. Association between proportion of gastroprotection, brand of electronic medical record (EMR), and type of GP practice were explored. Temporal trends in proportion of gastroprotection between electronic medical records systems were analyzed using a random effects linear regression model. Results We included 91,521 patient visits with NSAID prescriptions from 77 general practices between 2005 and 2010. Overall proportion of NSAID prescriptions to the elderly with co-prescription of gastroprotective medication was 43%. Mean proportion of gastroprotection increased from 27% (CI 25–29%) in the first quarter of 2005 with a rate of 1.2% every 3 months to 55%(CI 52–58%) at the end of 2010. Brand of EMR and type of GP practice were independently associated with co-prescription of gastroprotection. Conclusion Although prescription of gastroprotective medications to elderly patients who receive NSAIDs increased in The Netherlands, they are not co-prescribed in about half of the indicated cases. Brand of EMR system is associated with differences in prescription of gastroprotective medication. Optimal design and utilization of EMRs is a potential area of intervention to improve quality of prescription.

Feasibility of automatic evaluation of clinical rules in general practice

PURPOSE To assess the extent to which clinical rules (CRs) can be implemented for automatic evaluation of quality of care in general practice. METHODS We assessed 81 clinical rules (CRs) adapted from a subset of Assessing Care of Vulnerable Elders (ACOVE) clinical rules, against Dutch College of General Practitioners (NHG) data model. Each CR was analyzed using the Logical Elements Rule METHOD: (LERM). LERM is a stepwise method of assessing and formalizing clinical rules for decision support. Clinical rules that satisfied the criteria outlined in the LERM method were judged to be implementable in automatic evaluation in general practice. RESULTS Thirty-three out of 81 (40.7%) Dutch-translated ACOVE clinical rules can be automatically evaluated in electronic medical record systems. Seven out of 7 CRs (100%) in the domain of diabetes can be automatically evaluated, 9/17 (52.9%) in medication use, 5/10 (50%) in depression care, 3/6 (50%) in nutrition care, 6/13 (46.1%) in dementia care, 1/6 (16.6%) in end of life care, 2/13 (15.3%) in continuity of care, and 0/9 (0%) in the fall-related care. Lack of documentation of care activities between primary and secondary health facilities and ambiguous formulation of clinical rules were the main reasons for the inability to automate the clinical rules. CONCLUSION Approximately two-fifths of the primary care Dutch ACOVE-based clinical rules can be automatically evaluated. Clear definition of clinical rules, improved GP database design and electronic linkage of primary and secondary healthcare facilities can improve prospects of automatic assessment of quality of care. These findings are relevant especially because the Netherlands has very high automation of primary care.

Application of the logical elements rule method for formalization of clinical rules : case study of ACOVE-NLI

The Logical Elements Rule Method (LERM) is a step-wise method for formalizing if-then clinical rules. We applied LERM to a set of 40 clinical rules used in pharmacological quality assessment initiatives to assess (1) the amenability of the rules to formalization for decision support application (2) comparing adherence to rules that can and cannot be formalized, and (3) the usefulness of LERM as a tool for this task. Five rules could not be formalized, all due to unclear decision criteria. The adherence to ambiguous, non-formalizable rules was significantly lower than for formalizable ones (<0.001). We modified LERM with three additions for this task: (a) adding the sub-step of restating the rules in a consistent natural-language grammar before decomposing them into normal form, (b) creating rules to use in lieu of a controlled vocabulary, and (c) adding the requirement that a time frame must be defined for all medications (before hospitalization, current medication, new medication, or discharge medication). Although the clinical rules in this sample are all stated as semi-structured if-then recommendations and are used in quality assessment initiatives, many ambiguities and inconsistencies in the clinical rules were identified by using LERM.

Erratum to “Feasibility of automatic evaluation of clinical rules in general practice” [Int. J. Med. Inform. 100 (2017) 90–94]

Please cite this article in press as: D. Opondo, et al., Erratum to “Feasibility of automatic evaluation of clinical rules in general practice” [Int. J. Med. Inform. (2017) 90–94], Int. J. Med. Inform. (2017), http://dx.doi.org/10.1016/j.ijmedinf.2017.03.014 The publisher regrets that the name of author Ameen Abu-Hanna (Abu-Hanna, A.) was previously shown incorrectly as Hanna, A.A. This as now been corrected. The publisher would like to apologise for any inconvenience caused.