BackgroundVaccination registries have undoubtedly proven useful for estimating vaccination coverage as well as examining vaccine safety and effectiveness. However, their use for population health research is often limited. The Bacillus Calmette-Guérin (BCG) Vaccination Registry for the Canadian province of Québec comprises some 4 million vaccination records (1926-1992). This registry represents a unique opportunity to study potential associations between BCG vaccination and various health outcomes. So far, such studies have been hampered by the absence of a computerized version of the registry. We determined the completeness and accuracy of the recently computerized BCG Vaccination Registry, as well as examined its linkability with demographic and administrative medical databases.MethodsTwo systematically selected verification samples, each representing ~0.1% of the registry, were used to ascertain accuracy and completeness of the electronic BCG Vaccination Registry. Agreement between the paper [listings (n = 4,987 records) and vaccination certificates (n = 4,709 records)] and electronic formats was determined along several nominal and BCG-related variables. Linkage feasibility with the Birth Registry (probabilistic approach) and provincial Healthcare Registration File (deterministic approach) was examined using nominal identifiers for a random sample of 3,500 individuals born from 1961 to 1974 and BCG vaccinated between 1970 and 1974.ResultsExact agreement was observed for 99.6% and 81.5% of records upon comparing, respectively, the paper listings and vaccination certificates to their corresponding computerized records. The proportion of successful linkage was 77% with the Birth Registry, 70% with the Healthcare Registration File, 57% with both, and varied by birth year.ConclusionsComputerization of this Registry yielded excellent results. The registry was complete and accurate, and linkage with administrative databases was highly feasible. This study represents the first step towards assembling large scale population-based epidemiological studies which will enable filling important knowledge gaps on the potential health effects of early life non-specific stimulation of the immune function, as resulting from BCG vaccination.

BackgroundCystic renal cell carcinoma (CRCC) is relatively rare; CRCC is frequently misdiagnosed as a benign renal cyst. CRCC carries an excellent prognosis following surgical treatment. The aim of our study was to summarize the management of CRCC and to characterize the prognosis of affected patients.MethodsA retrospective study of 67 patients with CRCC was conducted at our center between January 2005 and April 2013. Patient prognosis as well as the clinical manifestations, imaging characteristics, treatment, and pathologic features of CRCC were summarized based on available medical record data.ResultsWe identified 67 cases of CRCC, representing 2.5% of all renal cell carcinoma cases. The tumor was discovered incidentally in 70% of the cases. Ultrasonography was found to be a useful screening tool, but computed tomography remains the imaging study of choice for identifying malignant features. Magnetic resonance imaging can be used in equivocal cases. Regarding treatment, radical nephrectomy was performed in 52% of the cases, and partial nephrectomy was selected in the remaining 48% of cases. None of the 46 patients (68% of the study group) available for follow-up showed any evidence of recurrence.ConclusionsCRCC is an uncommon subtype of renal cell carcinoma, occurring in 2.5% of cases. CRCC carries an excellent prognosis after surgical treatment. Partial nephrectomy should be regarded as the preferred surgical technique for CRCC.