Lemaitre 2009.

Methods	Purpose: to assess the effect of staff and resident influenza vaccination on resident all‐cause mortality Design: C‐RCT. A written invitation was sent to the 376 nursing homes with 50 to 200 elderly people (out of a total 1105 nursing homes) in the Paris area and 88 responded. Of these, 40 with staff influenza coverage < 40% during the 2005 to 2006 winter season were selected. Each institution was pair‐matched on size, staff vaccination coverage 2005 to 2006 and Group Iso Resources (GIR) weighted average disability score (which ranges from 1 = severe disability to 6 = total autonomy). Randomisation was centrally based using a random number generator Statistics: it was assumed that the influenza epidemic would last 2 months, mortality would be 8% in the control arm and resident mortality would be reduced 40% after staff vaccination to 4.8% in the intervention arm. 20 pairs of nursing homes with 2000 residents in each group were required to obtain 80% power with 2‐tailed hypothesis testing. Analysis was by intention‐to‐treat. "Odds ratios were calculated using alternating logistic regression, with one‐nested log odds ratios to model the association between the responses of the same pair and the same nursing home within the pair." "In secondary analyses, multivariate estimates were adjusted for the residents' age, vaccination status, GIR disability score and Charlson comorbidity index."
Participants	Country: France Setting: 40 nursing homes near Paris Eligible participants: 3483 patients in the 40 nursing homes In the intervention arm there were 1592 residents at the beginning and 130 entered the homes during the study period (total = 1722); 989 staff were present at recruitment and 678 (68.6%) were vaccinated. In the control arm there were 1558 residents at the beginning and 120 entered the homes during the study period (total = 1678); there were 1015 staff at recruitment and 323 (31.8%) were vaccinated 1452 (84.3%) of patients in the intervention and 1385 (82.5%) in the control group were vaccinated during the 2005 to 2006 winter season Age: 86 Gender: 77.% F
Interventions	Intervention: Promotional campaign with posters, leaflets and an information meeting with the study team to sensitise staff to the benefits of influenza vaccination for oneself and residents Face‐to‐face interviews with each member of staff present in nursing homes between 6 November and 15 December 2006 The study team met all administrative staff, technicians and caregivers to invite them to participate and those who volunteered were vaccinated at the end of the interview. The vaccine was inactivated Influvac (Solvay Pharma Laboratories), with 15 µG of each of A/Wisconsin/67/2005‐like (H3N2), A/New Caledonia/20/99 (H1NH1) and B/Malaysia/2506/2004 Control: routine information on influenza vaccination
Outcomes	Primary: all‐cause mortality Secondary: Influenza, measured when clusters of ILI occurred in residents, using the Quick View Influenza Test ILI ("defined as a fever of ≥ 37.8°C and onset of respiratory symptoms or worsening of chronic respiratory conditions" Proportion of staff who reported ≥ 1 day of sick leave
Notes	Design effect: 1.9; source: reported in published paper and confirmed by Magali Lemaitre Choice of main outcome is inappropriate
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Randomisation was centrally based using a random‐number generator"
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not stated
Incomplete outcome data (attrition bias) All outcomes	Low risk	During primary study period. Intervention group: 1592 residents at beginning + 130 entered and 1722 analysed; Control group: 1558 residents at the beginning, 120 entered, 1678 analysed (no statement of deaths or separations) Intervention group 989 staff (678 vaccinated); control group 1015 staff (estimated vaccination rate 31.8%)
Selective reporting (reporting bias)	Low risk	No selective reporting
Other bias	High risk	Performance bias (delivery of influenza vaccine to intervention arm)