The purpose of this study is to test the feasibility of a RCT of a new treatment for children and adolescents with eating disorders characterized by dietary restriction and/or weight loss or failure to gain expected weight. The treatment, which is called Family-Based Treatment for Primary Care (or FBT-PC for short), is based on Family-Based Treatment, the gold standard outpatient eating disorder treatment for children and adolescents.

In the United States, half a million adolescents suffer from an eating disorder. With only 66 certified providers nationally, Family-Based Treatment (FBT), a first-line evidence-based treatment for adolescent eating disorders, is not readily available to most families. This provider shortage leaves most young patients without care and undoubtedly contributes to the chronicity and lethality of these conditions. Patients with eating disorders generally make their first contact with the healthcare system in primary care. As such, equipping primary care providers (PCPs) with effective means to treat these patients has potential to democratize care, improve rates of early intervention, and enhance patient outcomes. Family-Based Treatment for Primary Care (FBT-PC) is a novel intervention for delivery by a PCP in primary care that uses FBT strategies. Data support proof-of-concept for this adaptation. This study has several study aims. (1) Finalize the FB-PC intervention through an open case series. (2) Establish the feasibility and acceptability of FBT-PC for caregivers, patients, and PCPs in a pilot randomized controlled trial. Finally, (3) to test preliminary target engagement of FBT-PC and determine whether it is associated with improved caregiver self-efficacy and, through this mechanism, symptom remission. Remission will be defined as weight restoration to 95% of expected body weight and a score within 1 SD of community norms on the Eating Disorder Examination-Questionnaire. In addition, as (4) an exploratory aim analyses will be conducted to evaluate baseline characteristics of the sample to determine for whom the FBT-PC intervention is most beneficial. To accomplish all aims an open case series (n = 6) will be conducted, followed by a pilot trial in which 40 patients (ages 7-18 years) with restrictive eating disorders and their caregiver(s) will be randomly assigned to FBT-PC or a control condition of standard FBT. Families will attend up to 18 sessions over 6 months. Goals from the open case series (Aim 1) will include the development of tools for FBT-PC training and implementation, including treatment and training protocols and fidelity measures. Feasibility (Aim 2) will be assessed through an evaluation of recruitment and retention. Acceptability (Aim 2) will be evaluated using mixed methods surveys and interviews of caregivers, patients and PCPs on the topics of tolerability, fit, and burden. The degree to which FBT-PC engages the proposed mechanism of change, caregiver self-efficacy, to facilitate symptom remission will also be assessed (Aim 3). Effect sizes will be calculated for FBT-PC with a goal of ≥ 0.5, comparable with those found in FBT trials. Finally, baseline sample characteristics (Exploratory Aim) will be assessed including caregiver perceptions about their child's illness, referral method, length of illness, and symptom severity. Once feasibility, acceptability, and target engagement of the FBT-PC intervention have been established, these findings will be used in support of a large pragmatic clinical trial to evaluate the noninferiority of effectiveness of FBT-PC versus standard FBT.

Inclusion Criteria:

• Diagnosis of a DSM-5 restrictive eating disorder (anorexia nervosa or other specified feeding or eating disorder characterized by dietary restriction and/or weight loss or failure to make expected weight gains).
• Eligible patients will have at least one caregiver who is also willing to participate in the study.
• Eligible patients must receive primary care through the MCHS

Exclusion Criteria:

• Patients will be excluded who have received FBT in the past, and/or who report active suicidality.
• Patients who become physically or psychiatrically unstable during the study will be re-evaluated and referred for appropriate treatment.
• Patients will be excluded if their enrolled caregiver has active substance dependence, mental health concerns that make it difficult to engage in treatment, or are perpetrators of abuse.