English to Italian Medical Medical (general) Studio clinico

Articolo scientifico relativo a uno studio osservazionale.
Frase:
In the present observational, matched-cohort, register-linkage study of COPD patients with a follow-up period of up to 11 years

Il linkage di cui si parla si riferisce a:
Data from primary care medical records were linked to those from Swedish national hospital, drug and cause of death registers.
Concetto ripetuto qui:
The linkage of data obtained from the national registers and primary care centres was performed by the Swedish National Board of Health and Welfare.

In queste frasi pensavo di utilizzare "i dati sono stati correlati/incrociati" e "la correlazione/l'incrocio dei dati". Ma per "register-linkage study" non trovo una formula stringata con riferimenti in rete.

Grazie.