Design and statistical analysis reporting among interrupted time series studies in drug utilization research: a cross-sectional survey

Table 1 General characteristics of included ITS studies (N=153)

Characteristics	n	%
Study sites
Multi-sites	108	70.6
Single-site	45	29.4
Data source^a
Hospital data (from electronic medical record)	60	39.2
Other administrative databases	54	35.3
Insurance (claims) database	27	17.6
Others^b	12	7.8
Intervention stages
Single	126	82.4
Multiple	27	17.6
Type of intervention
Prescription restriction	45	29.4
Drug price change (price, purchase or reimbursement policy)	27	17.6
Clinical guideline change (guidelines, statements or publications)	23	15.0
Education or training for physicians	22	14.4
Digital technology	13	8.5
Drug safety advisory	13	8.5
Drug approval or withdrawal	8	5.2
Others^c	2	1.3
Level of intervention
National	90	58.8
Hospital	30	19.6
State or province	21	13.7
Region	6	3.9
Others^d	6	3.9
Measure type of outcome
Drug utilization	125	81.7
Health outcomes	17	11.1
Expenditures	10	6.5
Others^e	1	0.7
Data type of outcome
Rate	98	64.1
Continuous	38	24.8
Count	15	9.8
Binary	2	1.3

^aAdministrative medical databases are massive repositories of data collected in healthcare for various purposes. Such databases are maintained in hospitals, health maintenance organizations and health insurance organizations. In this article, other administrative databases in this article included the administrative database which was not from hospital or health insurance organizations
^bOthers included registry (6 studies), survey (3 studies), statistical yearbook (2 studies) and cohort study (1 study)
^cOthers included drug shortage (1 study) and change drug packaging (1 study)
^dOthers included Europe (4 studies), city (1 study) and community (1 study)
^eOthers included cannabis-related criminal offences (1 study)

ISSN: 1471-2288