The phrase 'middle age group' is correct and usable in written English.
You can use it to refer to people of a certain age range. For example, "This survey is aimed at gathering information about the preferences of the middle age group."
Perceived stress was higher among the middle age group.
Data use was highest in the oldest age group, whereas Wi-Fi use was highest in the middle age group.
The number of SMS was higher in females (GM ratio 1.46) and the middle age group (15 19 year olds: GM ratio 2.21 compared to 10 14 year olds) and decreased over time.
Segmentation of the price attribute by demographic sectors reveals that those in the higher income bracket, higher education sector, middle age group, and who are male, had a higher marginal valuation on price.
And the middle age group is belatedly feeling a bit better off.
We have a middle age group in the squad, a group of players who have had terrific seasons.
Hence, the lower GOHAI score of disaster survivors particularly among the upper-middle age group, might be characteristic of victims from a disaster area.
There were significant differences in the frequencies of MSD between the young/middle age-group and the old age-group in most locations, while the only significant difference between the young and the middle age-group was found for shoulder-MSD.
A second weight was computed because the within-household screening deliberately introduced unequal probabilities of selection across the three age-groups to oversample the middle age-group.
When data were stratified by age groups, the middle age-group 30-400 years) had a rate of convictions similar to the mean of the total cohort.
In the middle-age group, the OR was 6.81 for mortality in patients with a combination of obesity and diabetes and 6.10 in those with a combination of heart disease and diabetes.
