Table 1.

Overview of study phases

Phase	Research question	Methods	Target population/data resource	Measures
A	What are the current practices (before-implementation) and the adherence to the delirium guideline in the participating ICUs?	Prospective, descriptive study, analyzing variation of care	Data from 6 ICUs	Indicators e.g.:
				??-Adherence to delirium screening
				??-Incidence of delirium
				??-Pharmacological treatment
				??-Sedation practices
				??-Non-pharmacological treatment
				??-Knowledge
B	What are the influencing factors (barriers and facilitators) for the implementation of the Dutch ICU delirium guideline by intensivists, ICU nurses, and psychiatrists?	Survey on knowledge, attitudes and perceptions, and structured focus group interviews	Health care professionals: intensivists, residents, ICU nurses, managers and psychiatrists, geriatrist or neurologist	Barriers and facilitators classified as related to: 1) guideline; 2) provider characteristics (e.g. knowledge and attitudes); 3) institutional characteristics (e.g. organization, structure, resources); 4) implementation (e.g. how and to what extent the guideline is implemented); 5) patient characteristics; and 6) social context (e.g. ICU culture).
C	What is the content of a tailored strategy to improve the adherence to the delirium guideline?	Strategy development according to implementation frameworks by Grol and Wensing, and Cabana	Matching the data from the current practice, questionnaires and focus groups and questionnaires to construct effective implementation strategies from the literature	Tailored multifaceted implementation strategy to effectively implement current guideline based delirium management
D	What is the effect of the tailored implementation strategy on guideline adherence, knowledge of health care providers, delirium incidence, clinical outcomes (mortality, length of stay) and health care costs?	Prospective before-after study	Data from 6 ICUs	(Process) indicators e.g.:
				-Adherence delirium screening
				-Incidence of delirium
				-Pharmacological treatment
				-Non-pharmacological treatment
				-Knowledge
				Outcomes e.g.:
				-Length of stay
				-Hospital mortality
				Costs
D	Explore potential explanations for why the intervention was effective or not based on ICU and health care providers' characteristics indicative of local ‘culture’.	Process evaluation: qualitative (outcomes,) and quantitative data (survey and interviews)	Data from 6 ICUs. Frame work for process evaluation, matching outcomes with actual exposure, and experiences of the implementation strategy	Underlying mechanisms that explain the effects of the study.