The phrase "a two year lag" is correct and usable in written English.
It can be used to describe a delay or gap of two years in a process, event, or data comparison.
Example: "The study revealed that there is a two year lag in the implementation of new policies compared to the initial recommendations."
Alternatives: "a two-year delay" or "a two-year gap."
As opposed to the previous study, 8 our study focused on long term risks; we applied a two year lag time, during which a large peak in incidence was observed.
Because lack of physical activity may indicate frailty and severity of diseases, we also performed further sensitivity analyses adjusting for physical activity with a two year lag or excluding participants in the lowest fifth of physical activity.
To exclude prevalent cases, we introduced a two year lag period from 2001 (first year of data in the Outpatient Register) such that the study period for our main analysis started in 2003.
Although we found a suggestion of increased risk of childhood cancer after exposure to ultrasound scans in early infancy, this association was attenuated and no longer statistically significant when we introduced a two year lag for exposure to scans (table 5).
Results were also similar after excluding participants with food frequency questionnaires returned within 12 months of initial onset of MI, excluding participants in the lowest fifth of physical activity, using a two year lag for physical activity or additionally adjusting for β blocker use (data not shown).
We also collected data quantifying the level of these variables between 1996 and 1999 in view of investigating their potential short term effect (defined here as a two year lag) or medium term effect (defined here as a four year lag) on the mortality rate in under 5s.
Strongest correlations were obtained between average annual WT measured at the bog margin and total P-PET over 7 years (r = 0.923, p < 0.00001), as well as between modelled WT and standardized TRW data with a two years lag (r = −0.602, p < 0.001) for those periods where WT fluctuated at the level of pine roots which is typically at <50 cm depth below the peat surface.
The introduction of area payment (indicator 10) seems to have had a positive effect in Poland (area payments introduced in 1999) and to some extent in Estonia and Latvia (area payments introduced in 2000 and 2001 respectively) whereas for Lithuania there is a ten year lag (area payments introduced in 1993).
We made the a priori assumption of a five year lag between exposure and outcome.
Web figure D shows corresponding results based on a five year lag period.
Associations were slightly smaller in magnitude under a five year lag, and model goodness of fit was poorer than that obtained under our a priori 10 year lag assumption.
