Firm specific identification codes made it possible to combine the information in both registers at the firm level.
The Social Insurance Institution register was merged with the Statistics Finland data at the Statistics Finland by using firm-specific identification codes.
These admissions were linked to the cohort of 23,172 patients with linkage variables 'date of birth', 'gender' and one or both of the variables 'numerical part of postal code' and 'hospital-specific patient identification code'.
For each hospital admission a new record is created in the hospital register, including the following information: date of birth, gender, numeric part of postal code, hospital-specific patient identification code, type of hospital, admission date and principal and secondary diagnoses of the admission.
For each hospital admission, a record is created in the HDR that includes information on date of birth, sex, numeric part of postal code (since 1991), hospital-specific patient identification code, type of hospital, admission date and principal diagnosis of the admission.
For each hospital admission a new record is created in the hospital register, including the following information: date of birth, gender, numeric part of postal code (since 1991), hospital-specific patient identification code, type of hospital, admission date and principal diagnosis of the admission.
Significantly, higher rates of vaccination (for under 65s) occurred in practices that identified appointments for flu vaccination using a specific Read (computer identification) code (p=0.038).
Study-specific patient identification codes were assigned and transmitted in such a manner that patient confidentiality was preserved.
The algorithm includes an ASHIP-specific, non-changing password to generate a truncated patient-specific identification (hash) code.
The proposed procedure integrated LDR for multiplicity and specificity, PCR amplification by universal primers for sensitivity, which required design of upstream and downstream LDR probes specific for each virus, and subsequent Zip-code microarray for multiplex and specific identification.
As the patients' identification code is generated from an ASHIP-specific algorithm, data can be assigned to a single patient only within his/her associated ASHIP but not across ASHIPs.
