1. Chatila, W.M., Thomashow, B.M., Minai, O.A., Criner, G.J. & Make, B.J. (2008) Comorbidities in chronic obstructive pulmonary disease. Proc. Am. Thorac. Soc., 5, 549-555.
2. Cheng, C.L., Kao, Y.H., Lin, S.J., Lee, C.H. & Lai, M.L. (2011) Validation of the National Health Insurance Research Database with ischemic stroke cases in Taiwan. Pharmacoepidemiol. Drug Saf., 20, 236-242.
3. Cutler, S.J. & Ederer, F. (1958) Maximum utilization of the life table method in analyzing survival. J. Chronic Dis., 8, 699-712.
4. Donaldson, G.C. & Wedzicha, J.A. (2006) COPD exacerbations. 1: Epidemiology. Thorax, 61, 164-168.
5. Hole, D.J., Watt, G.C., Davey-Smith, G., Hart, C.L., Gillis, C.R. & Hawthorne, V.M. (1996) Impaired lung function and mortality risk in men and women: findings from the Renfrew and Paisley prospective population study. BMJ, 313, 711-715.