Additional impact of concomitant hypertension and osteoarthritis on quality of life among patients with type 2 diabetes in primary care in Germany: a cross-sectional survey - Miksch, Antje; Krug, Katja; Rölz, Andreas; Joos, Stefanie; Szecsenyi, Joachim; Ose, Dominik; Rosemann, Thomas (BioMed Central, 2009)