Our healthcare solutions revenue grew almost about 37% organically in the quarter as we continued on the double-digit growth trajectory we started to see in the third quarter. Overall, our organic revenue growth was 7.6% in the quarter and for the full-year.
Decision Analytics organic growth in Q4 was 11%, driven by both strong growth from insurance-facing solutions as well as the accelerated growth in healthcare. The mortgage market remained challenging with the macroeconomic conditions continuing to work against us. We continue to have conviction around our margin and overall profitability. We are pleased to deliver 25% growth in diluted adjusted EPS for 2011 and over 16% growth in EBITDA, while expanding margins to over 46% excluding the recent acquisitions.
As always, we remained focused on delivering shareholder returns. We remained determined to find attractive M&A opportunities to take advantage of our substantial balance sheet flexibility. We bought $41 million of shares in the quarter, a lower amount than in previous quarters as we managed our buyback as part of our broader capital allocation plan including acquisitions.
We remained interested in using our capital as appropriate for buybacks is evidenced by our $300 million new authorization announced in January 2012. As I look forward to 2012, I see a consistency in our business plan, but also new opportunities on the horizon.I have confidence, we can continue to execute on that plan and realize attractive growth from the insurance base. We have set our healthcare business on a positive path to continue to grow and expand its footprint. I also think 2012 will bring more opportunity in our supply chain business as we work to leave our solutions in analytics together and also continued to pursue acquisitions in the space. Mortgage is likely to remain a soft spot for 2012, but we are also ensuring that we use our skill sets in ways that meet the evolving needs of the mortgage market as well as across the broader financial services sector.