The phrase "a midpoint year" is correct and usable in written English.
It can be used to refer to a year that represents the middle point of a specific time period, such as a decade or an era.
Example: "The year 2015 was considered a midpoint year in the analysis of economic trends over the past decade."
Alternatives: "a central year" or "a median year".
Staging and prognostic factor data were not generally available from the BC Cancer Registry before 2010, but all breast cancer cases diagnosed in 2002 were staged as part of a quality control exercise and this midpoint year was used to represent the total cohort of 1998 2006.
The midpoint year was used in the model as a categorical variable grouped as pre-1990, 1990–1999, and 2000 present.
For case-control studies we use the midpoint year of the interviews, while for prospective studies, we use a survival-adjusted mid-point of the follow-up period.
The analysis of the determinants of the cost per claim in Nova Scotia presented here focuses on cost estimate 8, based on the regional health related CPI and using the midpoint year.
Midpoint year between initial-final plasma donation dates was 1994 among FPDs with known donation dates.
Among the 25960 with known plasma donation dates, the peak midpoint year between initial and final donations was 1994 (Figure 3).
Figure 3 (males) and Figure 4 (females) plot the individual rate estimates for never smokers by study midpoint year for the same four regions, with estimates for squamous and adeno distinguished by colour.
Figure 1 (males) and Figure 2 (females) plot the individual rate estimates for all lung cancer by study midpoint year separately for the four major regions: America, Europe, China and other Asian countries.
The relationship between years-since-introduction and naturalized, weed, or noxious status is described by a quasi-logistic curve with a midpoint around 65 years (Fig. 1).
Her exhibition in London this September marks a midpoint in her three-year project.
