**Contingency Contracts for Weight Gain of Patients with Anorexia Nervosa in Inpatient Therapy: Practice Styles of Specialized Centers**

**Katrin Ziser 1,\*, Katrin E. Giel 1, Gaby Resmark 1, Christoph Nikendei 2, Hans-Christoph Friederich 3, Stephan Herpertz 4, Matthias Rose 5, Martina de Zwaan 6, Jörn von Wietersheim 7, Almut Zeeck 8, Andreas Dinkel 9, Markus Burgmer 10, Bernd Löwe 11, Carina Sprute 12, Stephan Zipfel <sup>1</sup> and Florian Junne <sup>1</sup>**


Received: 1 August 2018; Accepted: 11 August 2018; Published: 14 August 2018

**Abstract:** The treatment of patients with anorexia nervosa (AN) is often challenging, due to a high degree of ambivalence towards recovery and weight gain these patients often express. One part of the multimodal treatment is the utilization of treatment contracts (i.e., contingency contracts) that aim to motivate patients to gain weight by applying positive and negative consequences for the (non-)achievement of weight goals. The main aim of this study is to assess and analyze current standards of contingency contracts' utilization in German eating disorder centers. *n* = 76 mental health professionals of twelve specialized university centers in Germany that are currently or were formerly treating patients with AN in an inpatient setting participated. Most experts use contingency contracts in their clinic with weekly weight goals ranging between 500 and 700 g. Overall effectiveness and significance of contingency contracts for the inpatient treatment of patients with AN was rated high. Typical characteristics of a contingency contract in specialized German university hospital centers, such as the most frequent consequences, are described. The survey results assist the planning of further studies aiming to improve the multimodal treatment of patients with AN. For clinical practice, using external motivators such as contingency contracts as well as targeting internal motivation (e.g., by using motivational interviewing) is proposed.

**Keywords:** Anorexia nervosa; treatment contracts; weight gain; inpatient treatment; survey

#### **1. Introduction**

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), anorexia nervosa (AN) is a mental disorder characterized by an intense fear of gaining weight and body image disturbances that lead to restricted food intake relative to the required food intake (restrictive subtype) or other behaviors promoting weight loss such as excessive exercising or purging behavior (binge-purge subtype) [1]. Despite a twelve-month prevalence rate of 0.8% within the German population, AN is one of the mental disorders with the highest mortality [2–4]. In the long term, only approximately half of patients completely recover, whereas roughly 20 percent develop a chronic form of the disorder [5,6]. It takes an average of five to six years to achieve complete recovery [2]. This reflects the challenges associated with treatment, resulting from a high degree of ambivalence towards recovery and weight gain patients with AN often express [7,8].

According to German treatment recommendations, patients with severe AN (Body Mass Index (BMI) < 15) are treated in inpatient settings that regard weight restoration as one of the focal points for recovery [9]. Initial weight gain and symptom-orientation have been shown to predict good outcomes [10,11]. Nonetheless, a study by Schlegl and colleagues suggests that about one third of patients with AN do not show a significant response to intensive inpatient treatment [12]. Thus, there is still room for improvement in inpatient treatment approaches for patients with AN [13].

One indispensable part of the multimodal treatment approach for patients with AN is the utilization of a treatment contract, which is implemented to induce motivation for weight gain. Treatment contracts are currently routinely used in the inpatient treatment of patients with AN in Germany [14–17]. They are verbal or written agreements with the patient that contain mostly, but not exclusively, weight goals. Frequently, they outline the amount of weight that should be gained in a defined period of time during the inpatient stay (e.g., each week). Positive consequences for reaching these weight goals and negative consequences for not fulfilling weight goals are determined. Treatment contracts to induce weight gain in patients with AN can also be called weight contracts or contingency contracts for weight gain.

A recent systematic review by our group showed that despite their routine usage in inpatient treatment, contingency contracts for weight gain are an understudied topic and the empirical evidence base is scarce [18]. The majority of publications included in our review were of rather historical nature with few current contributions. We could, however, identify a development from restrictive applications of treatment contracts, e.g., in the form of bed rest to more collaborative approaches. These collaborative approaches try to actively involve patients into the contingency contracting process, e.g., by negotiating terms of the contract or letting patients choose consequences.

In terms of clinical application, there is some guidance in available treatment manuals for AN [15,19] with written examples of contracts. However, this guidance seems to stem from clinical expertise which is valuable but not sufficient to ensure high treatment standards. Currently, it is unclear whether treatment manuals are used and if done so, how the contingency contract process is organized in German eating disorder centers.

The main aim of the present study is to assess and analyze the utilization of contingency contracts for weight gain in German university hospitals specializing in eating disorders by means of a survey. Current approaches used by these specialized centers for collaboration with the patient are investigated, as well as strategies to enhance the patients' autonomy and motivation in the treatment contract process. Experiences of mental health professionals during the treatment contract process are also described. Finally, as an exploratory question, the role of professional characteristics in the contingency contract process is examined.

#### **2. Experimental Section**

#### *2.1. Study Centers*

Twelve specialized university hospital centers in Germany were invited and participated in this multicenter study. Mental health professionals who are currently or were formerly treating patients with AN in an inpatient setting were eligible for participation.

## *2.2. Sample*

The study sample consists of *n* = 76 medical doctors and clinical psychologists between the ages of 24 and 60 (*M* = 37.95, *SD* = 8.28). For a detailed sample description, see Table 1.


**Table 1.** Demographic characteristics of the study sample (*n* = 76).

#### *2.3. Measures*

The online survey contained questions concerning the following topics: (1) demographic characteristics (including e.g., therapeutic orientation and clinical work experience); (2) questions about the utilization of and criteria for implementing contingency contracts into the inpatient treatment routine (e.g., percentage of patients that receive a contingency contract, timepoint of conclusion, duration, standardization of the procedure); (3) precise form of the contingency contract (e.g., verbal, written, freely formulated); (4) weight goals, control days and consequences for achieving or not achieving the weight goals; (5) circumstances that lead to a termination of contingency contracts; (6) experienced emotions of experts during the contingency contract process and appraisal of effectiveness. Items were either dichotomous (applicable–not applicable) or measured on a seven-point Likert scale (e.g., 1 never–7 always). All items relating to the contingency contract were newly developed for this survey.

After the demographic questions, a definition of contingency contracts in the context of inpatient treatment of patients with AN was given for clarification. Contingency contracts in the form of a weight contract were defined as follows: "A weight contract is a verbal or written agreement with a patient that determines weight changes and/or behavioral changes (e.g., eating behavior) that are linked to consequences for the patient."
