Data will be extracted from GP practices as early as March next year for the NHS's controversial Care.data programme.

The scheme will allow primary care data from GP practices to be shared with the new Health and Social Care Information Centre (HSCIC) and clinical care groups (CCGs), and eventually matched with secondary care data, anonymised and shared with clinical researchers.

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Many have questioned why the health service needs to obtain so much data from the UK's citizens, but the NHS has stood firm, telling Computing that the data will provide "an evidence base to support commissioners to develop better treatment and ways of working, leading to improved outcomes and quality of care for patients".

In papers that are to be presented at an HSCIC board meeting this week, the programme team claims that preparations for the planned extraction of primary care data are "well under way".

"A phased rollout is being readied over a three-month period with full extractions anticipated in May 2014 (first extraction from March) allowing time for the HSCIC to assess the quality of the data and the linkage before it is made available to commissioners in anonymised form," the paper says.

In addition, the HSCIC board's feedback on the data controller position is being discussed with the Information Commissioner's Office, the paper adds.

In the Care.data update, the team says that there will be a national leaflet drop to all households in England planned for January to notify them of the Care.data programme - a move that the NHS was initially unwilling to go ahead with. The NHS had suggested that GPs should raise public awareness on their own, but was heavily criticised for this approach.

In order to resolve any patient queries in relation to the leaflet, the paper says that a "patient information line" is being put in place.

Several areas are yet to be ironed out, including a £1 cost per record for researchers to access data sets proposed by NHS England. Discussions are under way between the HSCIC board and NHS England to resolve this issue.

The paper says that Care.data primary care extraction may not deliver on time due to "the unknown amount and complexity of defects that may occur during certification and first of type activities based on progress to date".

Daily calls are taking place with suppliers, it says, while the HSCIC is working with each supplier to apply the lessons learnt from previous incidents and phases.

Of most concern to the HSCIC is that the programme team is at risk of moving forward without an approved business case and funding stream. The funding source for the programme going forwards "is not yet confirmed", the paper says.