Table 1.

 Summary of substudies in evaluation of phase two of Safer Patients Initiative (SPI2)

Substudy and topic	Data source	Unit of analysis
Staff survey*
Staff morale, culture, and opinion	NHS national staff survey	Staff member
Quality of care: acute medical care*
In patients aged >65 with acute respiratory disease	Case note reviews (both explicit and implicit)	Patient
Quality of care: perioperative care*
In patients with total hip replacement and open colectomy	Explicit case note review	Patient
Clinical process measures*
Use of consumables for hand hygiene	National observation study of effectiveness of national “cleanyourhands” campaign	Hospital
Outcomes
Adverse events in patients aged >65 with acute respiratory disease*	Holistic case note review	Patient
Hospital mortality in patients aged >65 with acute respiratory disease*	Case note review	Patient
Intensive care unit mortality†	Routine data from intensive care national audit and research centre	Hospital
Infection rates associated with healthcare †	Routine data from Health Protection Agency	Hospital
Patient satisfaction*	NHS patient surveys	Patient‡

*Data collected and analysed centrally

†Data collected by hospital staff, then analysed centrally.

‡In SPI1 unit of analysis was “hospital” as, in that case, we did not have individual patient data.