The phrase "an additional factor is" is correct and usable in written English.
You can use it when introducing another element or consideration in a discussion or analysis.
Example: "In evaluating the project's success, an additional factor is the level of community engagement."
Alternatives: "another aspect is" or "a further consideration is".
Berhe believes that an additional factor is that western governments give Eritreans "special treatment" when considering asylum applications.
In urbanized communities an additional factor is involved: children have been shown to be effectively influenced by the language habits of their peer groups once they have made contacts with them in and out of school.
This suggests that an additional factor is limiting the target zone which may be the dynamic properties of TM.
We reported for the first time that an additional factor is the individual mouse selected as a source for the islets [20].
As briefly discussed above, we speculate that an additional factor is required in order to produce the odd sensation; difficulty in attributing our inappropriate motor behavior to exogenous and endogenous events.
Work to identify such an additional factor is in progress.
And an additional factor was at work.
When the quartiles were evaluated separately in both groups, an additional factor was added to ANOVA to take into account the different groups.
In the present study, thanks to determination of the reference level (video material), an additional factor was identified which consists of recording short-term activities with difficult-to-establish border points.
At each stage, an additional factor was added or removed to reach the best fitting model.
In order to avoid countries changing their LIFDC status too frequently - typically reflecting short-term, exogenous shocks - an additional factor was introduced in 2001.
