Date	Event	Description
7 February 2014	New search has been performed	A search of the Group's Cystic Fibrosis & Genetic Disorders Group's Cystic Fibrosis Trials Register did not identify and potentially eligible trials.
7 February 2014	New citation required but conclusions have not changed	Minor changes regarding the latest search date have been made throughout the review.
30 March 2011	New search has been performed	A search of the Group's Cystic Fibrosis Trials Register did not identify any potentially relevant trials.
12 August 2009	New citation required but conclusions have not changed	Dr Anton Tan is no longer a member of the review team.
12 August 2009	New search has been performed	A search of the Group's Cystic Fibrosis Trials Register did not identify any trials potentially eligible for inclusion in the review.
12 August 2009	Amended	Data for serological response which had been inappropriately presented in the meta‐analysis has now been presented in additional tables and narratively in the text of the Results section.
31 October 2008	Amended	Converted to new review format.
1 May 2007	New search has been performed	A search of the Group's Trials Register identified no new references for inclusion in the review. Note: A change in the lead author's surname to Dharmaraj (née Bhalla).
2 April 2006	New search has been performed	A new search of the Group's Trials Register was run, but no new references were identified. The cost of annual vaccination quoted in the section 'Implications for practice' has been updated.
2 May 2005	New search has been performed	Change of lead author from Dr Anton Tan to Dr Poonam Bhalla. Data previously entered into Statistical Analysis for the outcome 'Serological response to vaccination' for the Adlard 1987 trial have been removed. This was due to the fact that only means (without standard deviations) were reported and entered, thus generating no meaningful summary statistics. An 'Additional table' has been completed which reports these limited data that were previously entered into Statistical Analysis (Table 01).
1 January 2002	New search has been performed	The two additional studies found with literature search were the same two considered last year. Schaad 2000 has now published his study and the reference was updated accordingly. Doudounakis 2000 has presented the same study with people with cystic fibrosis from three to eight years on the European Respiratory Annual Congress 2001. This study compared two different dose regimen with the same influenza vaccine and was therefore again not eligible.
1 January 2001	New search has been performed	Two additional studies were considered for the review. However, Doudounakis 2000 was excluded as it compared two different dose regimes of the same influenza vaccination. The other study identified (Schaad 1997), which compared virosome to a sub unit vaccine, met the inclusion criteria and was incorporated into the analyses bringing the total of included studies for the review to four. Only minor changes have been made to the results with no impact on the review's recommendation for further study of influenza vaccination in people with CF.