Open Access Research article

The ecometric properties of a measurement instrument for prospective risk analysis in hospital departments

Steffie M van Schoten1*, Rebecca J Baines2, Peter Spreeuwenberg1, Martine C de Bruijne2, Peter P Groenewegen13, Jop Groeneweg45 and Cordula Wagner12

Author Affiliations

1 NIVEL – Netherlands Institute for Health Services Research, Otterstraat 118-124, PO Box 1568, Utrecht 3500 BN, Netherlands

2 Department of Public and Occupational Health & EMGO Institute for Health and Care Research, Vrije Universiteit Medical Center (VUmc), Amsterdam, The Netherlands

3 Department of Sociology, Department of Human Geography, Utrecht University, Utrecht, Netherlands

4 Faculty of Social and Behavioural Sciences, Cognitive Psychology, Leiden University, Leiden, Netherlands

5 TNO, Hoofddorp, Netherlands

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BMC Health Services Research 2014, 14:103  doi:10.1186/1472-6963-14-103

Published: 3 March 2014



Safety management systems have been set up in healthcare institutions to reduce the number of adverse events. Safety management systems use a combination of activities, such as identifying and assessing safety risks in the organizational processes through retrospective and prospective risk assessments. A complementary method to already existing prospective risk analysis methods is Tripod, which measures latent risk factors in organizations through staff questionnaires. The purpose of this study is to investigate whether Tripod can be used as a method for prospective risk analysis in hospitals and whether it can assess differences in risk factors between hospital departments.


Tripod measures risk factors in five organizational domains: (1) Procedures, (2) Training, (3) Communication, (4) Incompatible Goals and (5) Organization. Each domain is covered by 15 items in the questionnaire. A total of thirteen departments from two hospitals participated in this study. All healthcare staff working in the participating departments were approached. The multilevel method ecometrics was used to evaluate the validity and reliability of Tripod. Ecometrics was needed to ensure that the differences between departments were attributable to differences in risk at the departmental level and not to differences between individual perceptions of the healthcare staff.


A total of 626 healthcare staff completed the questionnaire, resulting in a response rate of 61.7%. Reliability coefficients were calculated for the individual level and department level. At the individual level, reliability coefficients ranged from 0.78 to 0.87, at the departmental level they ranged from 0.55 to 0.73. Intraclass correlations at the departmental level ranged from 3.7% to 8.5%, which indicate sufficient clustering of answers within departments. At both levels the domains from the questionnaire were positively interrelated and all significant.


The results of this study show that Tripod can be used as a method for prospective risk analysis in hospitals. Results of the questionnaire provide information about latent risk factors in hospital departments. However, this study also shows that there are indications that the method is not sensitive enough to detect differences between hospital departments. Therefore, it is important to be careful when interpreting differences in potential risks between departments when using Tripod.

Prospective risk; Prospective risk analysis; Risk factors; Ecometric; Patient safety; Adverse event; Hospitals