Diagnosis-based cohort augmentation using laboratory results data: The case of chronic kidney disease.

PURPOSE: In this report, we use data from FDA's Sentinel System to focus on how augmenting a diagnosis-based chronic kidney disease cohort with patients identified through laboratory results impacts cohort characteristics and outcomes. METHODS: We used data from 2 Data Partners. Patients were eligible if they were health plan members on January 1, 2012. We classified chronic kidney disease patients into mutually exclusive categories according to the hierarchy of (1) ICD-9-CM diagnosis (DXGroup), or (2) two estimated glomerular filtration rates <60 mL/min/1.73m2 , separated by at least 90 days (2-LabGroup), or (3) a single estimated glomerular filtration rates <60 mL/min/1.73m2 (1-LabGroup). We compared the groups on demographic, clinical, and health care utilization characteristics using pairwise standardized differences. We used Cox regression to compare the groups on mortality, adjusting for baseline covariates. RESULTS: We identified 209 864 patients: 107 607 in DxGroup (51%) and 102 257 (49%) from laboratory data alone. For every characteristic, the DxGroup was the sickest, followed by the 2-LabGroup and then the 1-LabGroup. The DxGroup was more likely to die than 2-LabGroup (hazard ratio [HR], 1.47; 95% CI, 1.22-1.77) at Site 1; that effect was observed, but attenuated, at Site 2 (HR, 1.16; 95% CI, 1.07-1.25). The DxGroup was more likely to die than the 1-LabGroup at Site 1 (HR, 1.36; 95% CI, 1.20-1.55), but not at Site 2 (HR, 0.94; 95% CI, 0.89-1.00). CONCLUSIONS: We suggest that drug safety researchers consider whether the method of cohort identification contributes to generalizability of safety findings.

Using a Handheld Device for Patient Data Collection: A Pilot for Medical Countermeasures Surveillance.

Medical countermeasures (MCMs) are medical products used during public health emergencies. This study, conducted within the Mini-Sentinel Initiative, sought to develop the patient identification and matching processes necessary to assess safety outcomes for MCMs. A handheld device was used to collect identifying information (e.g., name, birthdate, and sex) from the driver's licenses of 421 individuals presenting for routine care at their primary care medical office. Overall, 374 individuals (88.8%) could be linked to their electronic health data using driver's license information. The device was also pilot-tested at a seasonal influenza immunization clinic: detailed vaccine information (e.g., lot number and manufacturer) was captured with a high degree of accuracy. This investigation demonstrated that a handheld device is a feasible means of collecting patient identity and medical product receipt data. This capacity should be useful for safety surveillance of MCMs, particularly when dispensed in settings outside the traditional health-care delivery system.

Does KRAS testing in metastatic colorectal cancer impact overall survival? A comparative effectiveness study in a population-based sample.

PURPOSE: Epidermal growth factor receptor (EGFR) inhibitors are approved for treating metastatic colorectal cancer (CRC); KRAS mutation testing is recommended prior to treatment. We conducted a non-inferiority analysis to examine whether KRAS testing has impacted survival in CRC patients. PATIENTS AND METHODS: We included 1186 metastatic CRC cases from seven health plans. A cutpoint of July, 2008, was used to define two KRAS testing time period groups: "pre-testing" (n = 760 cases) and "post-testing" (n = 426 cases). Overall survival (OS) was estimated, and the difference in median OS between the groups was calculated. The lower bound of the one-sided 95% confidence interval (CI) for the difference in survival was used to test the null hypothesis of post-testing inferiority. Multivariable Cox regression models were constructed to adjust for covariates. RESULTS: The median unadjusted OS was 15.4 months (95% CI: 14.0-17.5) and 12.8 months (95% CI: 10.0-15.2) in the pre- and post-testing groups, respectively. The OS difference was -2.6 months with one-sided 95% lower confidence bound of -5.13 months, which was less than the non-inferiority margin (-5.0 months, unadjusted p = 0.06), leading to a failure to reject inferiority of OS in the post-testing period. In contrast, in the adjusted analysis, OS non-inferiority was identified in the post-testing period (p = 0.001). Sensitivity analyses using cutpoints before and after July, 2008, also met the criteria for non-inferiority. CONCLUSION: Implementation of KRAS testing did not influence CRC OS. Our data support the use of KRAS testing to guide administration of EGFR inhibitors for treatment of metastatic CRC without diminished OS.

Patient perceptions of surgical informed consent: is repeat back helpful or harmful?

BACKGROUND: Informed consent (IC)comprehension is suboptimal. Repeat back (RB)-asking the patient to repeat in their own words key elements of the consent-is believed to improve the consent process. OBJECTIVE: This study aims to assess the impact of RB on patient perceptions of surgical informed consent. DESIGN: Secondary analysis of a randomized trial. SUBJECTS: Elective surgical patients were consented using iMedConsent, the VA's computer-based IC platform. Patients were randomized to RB (IC could not be signed until the patient satisfactorily expressed key elements) or standard iMedConsent (no RB). MEASURES: A questionnaire was given immediately after IC assessing time for decision, satisfaction with and ease of understanding consent, and the amount of information provided about the proposed surgery (e.g., indications, benefits, risks, and alternatives). Groups were compared with Χ tests. RESULTS: We enrolled 575 subjects (276 RB and 299 no RB); 92% were men with a mean age of 61.6 years and high school level reading ability. The groups were comparable in their perceptions regarding time to make a decision (RB 88% Strongly Agree (SA), no RB 88% SA; P = 0.61), satisfaction with consent (RB 90% SA, no RB 87% SA; P = 0.27), ease of understanding (RB 69% SA, no RB 67% SA; P = 0.73) receipt of the right amount of information regarding the indications (RB 85% SA, no RB 87%; P = 0.61), the benefits (RB 87% SA, no RB 86% SA; P = 0.29), and the risks (RB 87% SA, no RB 84% SA; P = 0.19) of surgery. More of the RB group felt they received the right amount of information about alternatives to surgery (RB 80% SA) than did the no RB group (69% SA); P = 0.01. CONCLUSIONS: Patients were highly satisfied with RB during surgical IC RB is not detrimental to the consent process and may improve informed consent for surgery. TRIAL REGISTRATION: Clinical Trials Identifier NCT00288899 http://www.clinicaltrials.gov.

Predictors of comprehension during surgical informed consent.

BACKGROUND: Patient comprehension during surgical informed consent remains problematic. Using data from our randomized trial of methods to improve informed consent comprehension, we performed an additional analysis to define independent factors associated with improved patient understanding. STUDY DESIGN: Patients scheduled for 1 of 4 elective operations (total hip arthroplasty [n = 137], carotid endarterectomy [n = 178], laparoscopic cholecystectomy [n = 179], or radical prostatectomy [n = 81]) at 7 Department of Veterans Affairs (VA) medical centers were enrolled. All informed consent discussions were performed using iMedConsent (Dialog Medical), the VA's computerized informed consent platform. Using a unique module within iMedConsent, we randomized patients to repeat back (RB), requiring correct reiteration of procedure-specific facts, or standard (STD) iMedConsent. Patient comprehension was tested after the informed consent discussion using procedure-specific questionnaires. Time spent completing the informed consent process was measured using time stamps within iMedConsent. Multiple linear regression identified factors independently associated with improved comprehension. RESULTS: We enrolled 575 patients (276 RB, 299 standard); 93% were male, 74% were Caucasian, and 89% had at least a high school education. Independent factors associated with improved comprehension included race (p < 0.01), ethnicity (p < 0.05), age (p < 0.02), operation type (p < 0.01), group assignment (+/- RB; p < 0.05), and total consent time (p < 0.0001). Patient comprehension was maximized when informed consent took between 15 and 30 minutes. RB's positive impact on patient comprehension was weaker in the analysis including consent time. CONCLUSIONS: Comprehension during informed consent discussions may be limited in individuals with potential language difficulty due to ethnicity or education. Total consent time was the strongest predictor of patient comprehension. Affording adequate time for informed consent discussions and using informed consent adjuncts such as RB may enhance comprehension in such individuals.

Enhancement of surgical informed consent by addition of repeat back: a multicenter, randomized controlled clinical trial.

OBJECTIVE: In this randomized, controlled, unblinded trial, we sought to test Repeat Back's (RB) effect on comprehension following informed consent discussions. SUMMARY BACKGROUND DATA: RB has been suggested as a method to improve patient comprehension when obtaining informed consent. In this technique, patients are asked to recount what they have been told in the informed consent discussion. Despite preliminary data, this practice has not been evaluated in any large scale study. METHODS: This study was conducted in 7 Veterans Health Administration Medical Centers where informed consent is obtained using iMedConsent, the VA's computer based platform. Patients scheduled for elective surgeries were randomized to RB (a module added to the iMedConsent package) or standard iMedConsent (no RB). Comprehension was tested after the informed consent using procedure-specific questionnaires. Time stamps in the iMedConsent program estimated the time spent completing the informed consent process. Provider and patient satisfaction were measured using 5-point Likert scales. Statistical comparisons of groups were performed using t-tests and chi tests. RESULTS: A total of 575 patients were enrolled. In the RB group, providers spent 2.6 minutes longer (P < 0.0001) obtaining informed consent. The mean comprehension score was significantly higher in the RB group (71.4%) versus the no RB group (68.2%, P = 0.03); the effect was greatest in carotid endarterectomy patients (RB = 73.4% vs. no RB = 67.7%, P = 0.02). Quality of decision making was rated similarly. Providers were neutral to slightly favorable regarding RB. CONCLUSIONS: RB implemented within an electronic informed consent system improved patient comprehension. The additional time required was acceptable to providers. RB should be considered as an enhancement to surgical informed consent.This clinical trial was registered at http://www.clinicaltrials.gov (Identifier NCT00288899).