The purpose of this project is to test a brief, telephone-based psychological intervention, CBT-UT, to improve the ability to tolerate uncertainty-and thereby to reduce distress-in people with a recent diagnosis of Multiple Sclerosis (MS). There are three treatment arms for this study. Participants will receive either (1) CBT for Uncertainty Tolerance, (2) Traditional CBT, or (3) treatment as usual.

Despite substantial improvements in diagnosis and treatment, Multiple Sclerosis (MS) remains an unpredictable disease. Although some physicians can make some predictions about expected progression, the variable course of exacerbations makes it almost impossible to predict how MS will develop or affect function over time. As a result, people with MS must learn to live in a state of chronic uncertainty and the ability to tolerate and cope with this kind of uncertainty is central to quality of life with MS. Individuals who require certainty about the future and are not able to tolerate ambiguity are said to be high in a personality trait known as intolerance of uncertainty (IU). There is a significant gap in MS clinical intervention that necessitates attention. An intervention that specifically targets IU, is developed for people recently diagnosed with MS, and can be provided remotely via telehealth can make a significant impact for this population. Study aims include: (1) to determine the efficacy of CBT-UT relative to traditional cognitive behavioral therapy (tCBT) or treatment as usual (TAU) in people diagnosed with MS in the past 3 years; and (2) To increase our understanding of the mechanisms underlying the intervention effects.

Inclusion Criteria:

• Adults over 18 years of age
• MS diagnosis using revised McDonald Criteria
• Able to read, speak, and understand English
• At least mild psychological distress evidenced by (1) a score of 20 or higher on the Kessler Psychological Distress Scale OR (2) a score greater than or equal to 5 on the Perceived Stress Scale.

Exclusion Criteria:

• Severe cognitive impairment defined as one or more error on the Six-Item Screener
• Psychiatric condition or symptoms that would interfere with participation, specifically (1) current, active suicidal ideation with current intent to harm oneself, (2) current psychosis, or (3) current mania.

The investigators propose to make available to interested researchers a data file (de-identified to remove any variables from which it would be possible to identify any individual participant) any data used in a published article, at the time that it is accepted for publication. That is, at the request of an outside researcher, the investigators will create and share a data file that includes all of the variables used in the published article and a list of the variables in the data file (along with their variable labels). Any investigators who request these data will receive (1) a copy of the published article (which will describe the source of the data); (2) the variable list/variable labels; and (3) a data set.

Data will become available after the main study results are published.

Although any shared data will be stripped of identifiers prior to release, given the very specific nature of the study sample (individuals who have had a recent diagnosis of MS) it is possible that those who access this data could potentially identify subjects with unusual characteristics or combinations of unusual characteristics. Therefore, the investigators will make the data and associated documentation available to users only under a data-sharing agreement that provides for: (1) a commitment to using the data only for research purposes and not to identify any individual participant; (2) a commitment to securing the data using appropriate computer technology; and (3) a commitment to destroying or returning the data after analyses are completed.

Research manager will be blinded for this trial. Research coordinator and investigator will not.