1. Measures of general health status;Andresen,1997
2. Meta-analysis in clinical trials;DerSimonian;Controlled Clinical Trials,1986
3. See China's new situation of population aging from the data of the sixth population census;Du;Journal of Population Research,2011
4. Bias in meta-analysis detected by a simple, graphical test;Egger;British Medical Journal,1997
5. Coping with the empty nest situation as a developmental task for the aging female – An analysis of the literature;Fahrenberg;Zeitschrift Fur Gerontologie,1986