Purpose To validate Covid-19 information records in The Pharmacoepidemiological Research Database for Public Health System (BIFAP), commonly used for pharmacoepidemiological research in Spain. Methods The recorded Covid-19 cases in primary care (PC) or positive test registries (gold-standard) were identified among vaccinated patients against SARS-CoV-2 infection of any age. They were matched with unvaccinated controls by birth year, vaccination date, region, and sex, between December 2020-October 2021. The sensitivity (SE), specificity (SP), positive (PPV), negative (NPV) predictive values, and date accurateness were estimated for PC by vaccination status and age brands. Results Among 21,702 patients with positive tests and 20,866 with recorded Covid-19 diagnoses, the SE, SP, PPV, and NPV were, respectively, 79.98%, 99.95%, 80.24% and 99.94% among vaccinated, and 78.67%, 99.96%, 84.51% and 99.94% among controls. For those aged ≥70 years old, SE (71.15-72.85%) was lower while PPV (84.68-88.04%) was higher compared to <70 years old participants. 94.12% of the total true positive cases (N=17,191) were recorded within ±5 days from the date of the test result. Conclusions PC Covid-19 diagnosis recorded in BIFAP showed high validation parameters. SE was similar and PPV was slightly lower among vaccinated than unvaccinated controls. Correction of vaccines effectiveness estimates by such misclassification is recommended. Data shows the influence of age. Among the elderly, Covid-19 diagnosis was less recorded but when recorded is more accurate than among younger patients. These findings permit the design of informed algorithms for performing Covid-19-related research.

Objective To identify primary care recorded factors associated with the short-term human papillomavirus (HPV) vaccination among girls and female adolescents. Methods We used the Spanish Pharmacoepidemiological Research Database for Public Health System to identify girls aged 9-18 years in 2007-2016 with ≥1 year of primary care data (start date) and collect baseline characteristics and consultations. The link between those factors and the 1-year HPV vaccination was assessed through multivariate adjusted Odds Ratios (OR; 95% CI). Results Among 388,669 girls identified, 14,999 were vaccinated against HPV during the first year. The vaccination decreased among girls consulting for social (0.62; 0.55-0.70) or adaptation (0.60; 0.38-0.93) problems, prescriptions of benzodiazepines (0.58; 0.35-0.94) or drugs for gastrointestinal symptoms (0.58; 0.38-0.89), with recorded tuberculosis test (0.68; 0.52-0.87), B and C meningitis (0.46; 0.43-0.50) vaccination, consulting the doctor in the last 3 months (0.92; 0.87-0.98) and with severe thinness (0.68; 0.59-0.78) or obesity (0.88; 0.78-0.99). The odds increased among girls with abdominal pain (1.10; 1.04-1.16), prescriptions in the last 3 months (1.17; 1.10-1.25), and vaccinations against chickenpox (1.16; 1.07-1.27), influenza (1.23; 1.08-1.40), hepatitis (1.46; 1.35-1.58) and diphtheria-tetanus (1.91; 1.82-2.01). Conclusions The correlation between the HPV and other vaccinations suggested medical (contra)indications or willingness and knowledge/beliefs that might affect different vaccinations similarly. The higher frequency of the HPV vaccination among females requiring specific treatments or with abdominal pain suggested vulnerability to HPV complications. While a decreased HPV vaccination linked to certain social and personal situations (and benzodiazepines treatment) requires further research.