The phrase "assesses how often" is correct and usable in written English.
You can use it when discussing the frequency of an event or behavior in a formal or analytical context.
Example: "The study assesses how often participants engage in physical activity each week."
Alternatives: "evaluates the frequency of" or "measures how frequently".
This study assesses how often local US hospitals provide smoking cessation information in the following two ways: via hospital Web sites; and via routing incoming phone calls to their hospital switchboards to an in-house smoking cessation clinic.
Each item assesses how often a strategy is used to handle stress.
The PHQ-9 is a nine-item self-administered scale which assesses how often in the past 2 weeks participants have been bothered by a range of symptoms or problems.
Medication nonadherence was assessed by the eight-item Hill-Bone Compliance Scale (α = 0.80) (29), which assesses how often and why respondents miss taking medications as rated on a 4-point scale from none of the time to all of the time.
Medication adherence was assessed by the eight-item Hill-Bone Compliance Scale (α = 0.80) (31) that assesses how often and why respondents miss taking medications, rated on a 4-point scale from "none of the time" to "all of the time".
For each of the nine DSM-IV depression symptoms, the PHQ-9 assesses how often the respondent has been bothered by that symptom over the past two weeks, assigning values of 0 to 3 points (0 - not at all, 1 - several days, 2 - more than half of the days, 3 - nearly every day).
Gallup has asked 1,000 adults a day since mid-February of this year to assess how often they go to church.
The researchers did not assess how often the kids in the handwashing group actually washed their hands.
To assess how often horses break down or get injured, The Times purchased official data covering more than 150,000 race results from 2009 through 2011.
To assess how often patients receive dental implants after mandibular resection for benign neoplasms and to determine barriers to completion of functional reconstruction.
