对照人群 meaning in English

control population

The poor people was 237 and the control people was 261
其中被调查的贫困对象237人，对照人群261人。
The quality of life of poverty team was significantly differed with that of the control team . the change of health of the poor that is shown by the ht item is decreasing
将贫困人群与对照人群sf一36量表的健康变化( ht )进行比较，提示贫困人群健康变化有向差转变的趋势。