NORWALK, Conn. (AP) — Health care data company IMS Health Inc. said Tuesday it will hold a special meeting Feb. 8 to vote on a $4 billion buyout offer. On Nov. 5, the company said it will be bought by investment funds TPG Capital and CPP Investment Board in a leveraged buyout worth $22 per share, marking a 31 percent premium to IMS shares' closing price prior to the offer. Including assumed debt, the deal is valued at $5.2 billion. IMS stockholders of record at Dec. 28 will be entitled to vote in the special meeting being held at The Hyatt in Greenwich, Conn. The leveraged buyout deal has committed debt financing from the private-equity firms and Goldman Sachs affiliates. It has already been approved by the IMS board of directors. IMS tracks pharmaceutical prescriptions and sales, and counts some of the largest drug developers as its clients. The data is often used by Wall Street to gauge how well a specific product is selling. IMS also provides auditing services for the health care industry along with analysis tools. Shares of IMS rose 19 cents to close at $20.57.