The phrase "a key variable to" is correct and usable in written English.
It can be used when discussing an important factor or element that influences or contributes to a particular outcome or situation.
Example: "In our research, we identified a key variable to understanding the relationship between diet and health."
Alternatives: "a crucial factor in" or "an essential element for".
Therefore, parental education seems to be a key variable to understand the external circumstances that condition opportunities.
Teachers' information and communication technology (ICT) competences are a key variable to integrate such resources into the teaching-learning process.
Is project speed a key variable to be managed, or does it result from other project parameters?
Second, it permits to explore the behaviour of real wages in response to asymmetric shocks, as this is a key variable to allow the adjustment of relative unemployment rates.
As the case of China and the Philippines accounts well for why they could not stop driving each other closer to the point of armed collision, both the US and China find the failure of asymmetry management as a key variable to increase misperception and tension not only in SCS at a regional level but in East Asia at global levels.
The labor force participation rate (LFPR) -- the share of the 16 and up population either working or looking for work -- is a key variable to watch these days.
Tissue strain (defined as change in lung volume divided by initial volume) is a key variable at the tissue level to which several of those mechanisms of ventilator induced lung injury converge.
However, education – usually a key variable linked to electoral participation – is not significant for either electoral or non-electoral engagement.
In this experiment, using a key variable checklist to verify diagnostic decisions improved error detection.
We recognize that using a key variable checklist to improve decision verification requires identification of diagnostic task where the problem space is well defined and key variables can be identified (e.g., ECG interpretation, chest X-ray interpretation, or cardiac physical exam).
Height is a key variable that relates to many techniques of measuring of arterial stiffness since it is related to the timing of arterial wave reflections, and it is hardly surprising that this remains in the final model.
