Systematic Review of Interventions Used in or Relevant to Occupational Therapy for Children With Feeding Difficulties Ages Birth–5 Years

Research Design

This systematic review of the research literature was initiated and supported by the American Occupational Therapy Association (AOTA) as part of the Evidence-Based Practice Project. The review was carried out by identifying articles in two phases followed by a comprehensive review. The goal was to retrieve reports of research investigating the effectiveness of feeding interventions, relevant to or using occupational therapy, in the population ages birth–5 yr. Detailed information regarding the methodology for the entire literature review can be found in the article “Method for the Systematic Reviews on Occupational Therapy and Early Intervention and Early Childhood Services” in this issue (Arbesman, Lieberman, & Berlanstein, 2013).

Research Question

The following research question guided the selection of research studies for the review and the interpretation of the findings: What is the evidence for the effectiveness of interventions used in occupational therapy to improve feeding, eating, and swallowing for children from birth to age 5?

Procedures

In the first phase of the research, articles were identified by searching Medline, CINAHL, PsycInfo, ERIC, the Campbell Collaboration, and OTseeker. Hand searching of bibliographies and journals was performed as needed. The systematic review question and search terms were developed by the authors, AOTA staff, and the project consultant and were reviewed by an advisory group of occupational therapy practitioners, researchers, and educators. The search terms were used first individually and then in combination. A medical librarian with experience in systematic reviews completed the searches. The project consultant completed the initial review of titles and abstracts. We completed the final review of titles and abstracts.

Criteria for inclusion in this review were the following: (1) the reported intervention could be performed by occupational therapists in various settings; (2) articles were original scientific reports of studies of children from birth to age 5 yr with a developmental delay, disability, or condition that affects development; (3) articles were focused on evaluating the effects of the interventions in an effort to improve feeding and feeding-related performance; (4) at least one of the outcome measures was related to feeding behaviors (i.e., sucking, breast or bottle feeding, mealtime behavior, food intake); (5) studies were categorized as Level I, II, or III evidence or as Level IV evidence in areas without higher level evidence; (6) articles were published in English-language peer-reviewed journals; and (7) articles were published after 1990. The inclusion criteria were established by the authors, AOTA staff, and the project consultant on the basis of the focus of the study and to ensure that all related articles would be included.

The authors, AOTA staff, and the project consultant reviewed each article to identify the type of intervention and its relevance to occupational therapy. Reference lists of all identified articles were searched for additional articles that were missed in the keyword search. We performed a comprehensive review to seek evidence about the effectiveness of the identified intervention. In addition, sample size and sample characteristics of the retrieved studies were reviewed to determine whether they represented the target population. To ensure credibility of the data analysis in the reviewed articles, we studied each article individually and compared our draft findings. When agreement was reached, we developed and proposed major themes on the basis of the contents of retrieved articles and subsequently organized and compiled evidence tables on the basis of the results of the comprehensive review. Sample articles are presented in Supplemental Table 1 (available online at http://ajot.aotapress.net; navigate to this article, and click on “Supplemental Materials”), and a full evidence table is also available online as Supplemental Table 2. The tables and the articles included for systematic review were finalized after discussion among the authors, AOTA staff, and the project consultant to ensure accuracy of the descriptions of the studies and categorization of the themes.

Behavioral Interventions

Behavioral interventions were defined as treatment strategies based on operant learning principles. Treatment strategies include but are not limited to differential attention (Kerwin, 1999), positive reinforcement (Ahearn, Kerwin, Eicher, Shantz, & Swearingin, 1996; Byars et al., 2003; Kerwin, 1999), physical guidance (Ahearn et al., 1996; Kerwin, 1999; Williams, Riegel, Gibbons, & Field, 2007), extinction or flooding (Benoit, Wang, & Zlotkin, 2000; Byars et al., 2003; Schädler, Suss-Burghart, Toschke, von Voss, & von Kries, 2007; Williams et al., 2007), and shaping (Byars et al., 2003). Differential attention was defined as giving positive attention to appropriate feeding behavior and ignoring inappropriate behavior. An example of the application of positive reinforcement is the use of verbal praise or brief access to a preferred toy or activity immediately after achieving a targeted feeding behavior (i.e., self-feeding, food acceptance; Kerwin, 1999). An example of extinction is when the therapist keeps the spoon at the child’s lips (without the use of force) until the mouthful is accepted (Ahearn et al., 1996; Benoit et al., 2000). Because removing a spoon after refusal reinforces food refusal behaviors, nonremoval of the spoon is an extinction procedure (Benoit et al., 2000). Physical guidance refers to providing manual assistance with the appropriate feeding response after the occurrence of an incorrect response or after 40–60 s of no response (Kerwin, 1999).

Seven studies were categorized as research on behavioral interventions. Two Level I articles, 4 Level III articles, and 1 Level IV article were reviewed (Benoit et al., 2000; Byars et al., 2003; Greer, Gulotta, Masler, & Laud, 2008; Kerwin, 1999; Laud, Girolami, Boscoe, & Gulotta, 2009; Wilder, Normand, & Atwell, 2005; Williams et al., 2007).

Behavioral intervention strategies in the reviewed articles included positive and negative reinforcement, shaping, physical guidance, discrimination, fading, and escape extinction (Kerwin, 1999). The evidence from a review of Level I–III articles suggests that behavioral interventions are effective for children with a variety of feeding problems (Benoit et al., 2000; Byars et al., 2003; Greer et al., 2008; Kerwin, 1999; Laud et al., 2009; Williams et al., 2007). The evidence supports that behavioral interventions can improve acceptance of a variety of foods (Laud et al., 2009), mealtime behaviors (Greer et al., 2008; Kerwin, 1999; Laud et al., 2009), weight gain (Benoit et al., 2000; Byars et al., 2003; Greer et al., 2008), caloric intake (Benoit et al., 2000; Byars et al., 2003; Greer et al., 2008; Kerwin, 1999; Williams et al., 2007), and self-feeding skills (Kerwin, 1999). In addition, 2 Level III studies found that behavioral interventions were effective in decreasing caregivers’ stress (Greer et al., 2008; Laud et al., 2009).

In a systematic review (Level I evidence), Kerwin (1999) reported that positive reinforcement of appropriate feeding responses and ignoring or guiding inappropriate responses—for example, not removing the spoon for refusal and swallow induction training (as differential attention)—were effective interventions for children with severe feeding problems. Level I and Level III evidence supported the effectiveness of behavioral therapy in eliminating enteral feeding in children with resistance to oral feeding (Benoit et al., 2000; Byars et al., 2003).

Behavioral interventions have been reported to be effective for children with different diagnoses and across many settings. Participants included children dependent on tube feeding in inpatient or outpatient settings (Benoit et al., 2000; Byars et al., 2003; Greer et al., 2008; Williams et al., 2007); children with mental retardation across inpatient settings, residential and nonresidential schools, and institutions (Kerwin, 1999); children with Rett syndrome in an inpatient setting (Kerwin, 1999); children with autism spectrum disorder in an inpatient setting (Kerwin, 1999; Laud et al., 2009); and children with complex medical problems in an inpatient setting (Kerwin, 1999). Wilder et al. (2005) reported in their single-subject study conducted in an outpatient setting that a noncontingent reinforcement treatment was effective in decreasing self-injury behaviors and increased bite acceptance in a 3½-year-old child with autism, gastroesophageal reflux, and food allergies who exhibited food refusal. No studies in this review reported effective behavioral interventions delivered in home settings.

Parent-Directed and Educational Interventions

Feeding is often considered a dyadic process between a child and his or her caregiver, especially for younger children. Intervention strategies developed under this theoretical orientation often address children’s feeding problems by providing primary caregivers with information and recommendations regarding how to facilitate appropriate feeding behaviors. Studies conducted under this theoretical orientation were reviewed in the category of parent-directed or educational interventions.

Six studies addressed parent-directed and educational interventions. Four Level I studies (Black, Dubowitz, Hutcheson, Berenson-Howard, & Starr, 1995; Garcia Coll et al., 1996; Pinelli, Atkinson, & Saigal, 2001; Pridham et al., 2005) and 2 Level III studies (Chatoor, Hirsch, & Persinger, 1997; Fraser, Wallis, & St. John, 2004) were included in this category.

Evidence from the reviewed articles suggested that parent-directed and educational interventions for children with feeding problems are moderately to strongly effective in improving children’s physical growth and development, increasing the feeding competence of children and their primary caretakers, and improving parent–child interaction. Synthesis of these studies does not result in consensus on which form of delivering parent-directed intervention is preferred.

The research evidence supports a parent-directed and educational approach over regular care when delivered alone or in combination with regular care. Black et al. (1995) reported in their Level I study that combining family-focused intervention with regular care is more efficient than administering regular care alone with respect to improving growth, development, and interactive competence in children with nonorganic failure to thrive.

In addition, moderate to strong evidence has shown that parent-directed and educational interventions are effective in improving mother–infant interactions in a variety of populations (Black et al., 1995; Chatoor et al., 1997; Garcia Coll et al., 1996; Pridham et al., 2005). Pridham et al. (2005) demonstrated that an individualized relationship-based intervention (guided participation) is more effective than standard care in supporting feeding competency development for mothers and their premature infants. In their study, feeding competency included infant feeding skills as well as maternal and infant interaction.

Other researchers have reported that an individualized behavioral feeding intervention was effective in promoting physical growth and parent–infant interaction (Black et al., 1995; Chatoor et al., 1997; Garcia Coll et al., 1996). Black et al. (1995) demonstrated that 1 yr of combined clinic and home visits, compared with clinic visits only, was effective in improving physical growth and parent–infant interaction in children with nonorganic failure to thrive. In a short-term intervention to promote physical growth for full-term infants with intrauterine growth retardation, Garcia Coll et al. (1996) reported moderate effects when using education and demonstration and providing feedback on mother–infant feeding interaction. In addition, Chatoor et al. (1997) reported that a parent-centered intervention was effective for parents who had infants with infantile anorexia. The psychotherapeutic intervention for parents was effective in improving feeding interaction and infants’ internal regulation of eating.

No consensus exists to support any preferred forms of delivery for a parent-directed and educational intervention. In a Level I study, Pinelli and colleagues (2001) reported no significant difference in duration of breastfeeding between the supplementary structured breastfeeding counseling group and the conventional hospital breastfeeding support group. The counseling included weekly personal contact in the hospital and frequent contact after discharge for infants with birth weight <1,500 g through the infants’ 1st yr or until breastfeeding was discontinued. The conventional hospital breastfeeding support group had standard support confined to the period of hospitalization in the neonatal intensive care unit. Other evidence demonstrated that parent education programs that teach parenting strategies can be effective in improving children’s problems with eating and mealtime behavior (Fraser et al., 2004).

Physiological Interventions

Feeding can be viewed as a complex developmental skill that requires the integration of breathing, sucking, and swallowing in the context of overall motor stability and incoming sensory stimuli. Many studies have focused on increasing understanding of the effects of early physiological development on the complex task of coordinated feeding. In our review, interventions that concentrated on improving children’s biological development, including physical and sensory functions to support infant feeding, were categorized as physiological interventions.

Twenty-one studies were categorized as research on physiology-based interventions. Twelve Level I studies (Bier et al., 1996; Boiron, Da Nobrega, Roux, Henrot, & Saliba, 2007; Bragelien, Rokke, & Markestad, 2007; Fucile, Gisel, & Lau, 2002, 2005; Hake-Brooks & Anderson, 2008; Moore, Anderson, & Bergman, 2007; Pinelli & Symington, 2005; Reid, 2004; Rocha, Moreira, Pimenta, Ramos, & Lucena, 2007; Simpson, Schanler, & Lau, 2002; White-Traut et al., 2002), 3 Level II studies (Barlow, Finan, Lee, & Chu, 2008; Gaebler & Hanzlik, 1996; Poore, Zimmerman, Barlow, Wang, & Gu, 2008), 4 Level III studies (Einarsson-Backes, Deitz, Price, Glass, & Hays, 1994; Jadcherla et al., 2009; Lamm, De Felice, & Cargan, 2005; Munakata et al., 2008), and 2 Level IV studies (Gisel et al., 2003; Larnert & Ekberg, 1995) were reviewed.

Feeding is multifaceted. Studies in the category of physiology-based interventions can be further divided into three subcategories on the basis of their targeted behaviors. Subcategories include (1) studies targeting preparatory behaviors such as physiological stability for oral feeding (studies investigating the effects of skin-to-skin contact (SSC), nonnutritive sucking [NNS], or oral desensitization were included in this subcategory); (2) studies targeting the acquisition of feeding skills, including sucking and swallowing; and (3) studies targeting environmental support of feeding, including positioning and feeding devices.

Implications for Occupational Therapy Practice

Using the evidence presented in this review, clinicians may appreciate the merits of different approaches, understand which approach is most effective for certain target behaviors, and ascertain optimal settings for service delivery. For example, our review supports that behavioral interventions are effective in improving children’s appetite, acceptance of food (Laud et al., 2009), oral intake (Benoit et al., 2000; Byars et al., 2003; Greer et al., 2008; Kerwin, 1999), and mealtime behaviors (Greer et al., 2008; Kerwin, 1999; Laud et al., 2009). Parent-directed and educational interventions are reported to be an effective approach when the therapeutic goals are to improve maternal support, parenting skills, mother–child interaction (Black et al., 1995; Garcia Coll et al., 1996; Pridham et al., 2005), or the feeding competency of children and mothers (Pridham et al., 2005). Finally, physiological interventions are commonly used with preterm infants (Barlow et al., 2008; Boiron et al., 2007; Einarsson-Backes et al., 1994; Fucile et al., 2002, 2005; Gaebler & Hanzlik, 1996; Jadcherla et al., 2009; Pinelli & Symington, 2005; Poore et al., 2008; Rocha et al., 2007; Simpson et al., 2002; White-Traut et al., 2002), children with neuromuscular impairments (i.e., cerebral palsy, dysphagia; Gisel et al., 2003; Jadcherla et al., 2009; Lamm et al., 2005; Larnert & Ekberg, 1995; Munakata et al., 2008), or children with oral structure abnormalities (i.e., cleft palate; Reid, 2004) to improve feeding performance. In terms of service delivery settings, the interdisciplinary behavioral interventions were concluded to be effective when conducted in inpatient and outpatient settings (Benoit et al., 2000; Byars et al., 2003; Kerwin, 1999).

From the results, we see that a range of interventions for children with feeding difficulties are often used in combination. Garcia Coll and her colleagues (1996) conducted a behavioral feeding intervention with mothers of intrauterine growth–retarded infants. They combined both parent-directed and educational interventions and behavioral intervention by using operant learning principles of behavioral therapy such as positive reinforcement and shaping to facilitate parents’ optimal responses during feeding and indirectly worked on children’s feeding performance. Laud et al. (2009) and Williams et al. (2007) combined behavioral therapy with oral–motor therapy to improve food intake in children with various degrees of feeding disorders and children with autism spectrum disorder. Greer et al. (2008) combined all three approaches in their investigation of the effectiveness of an interdisciplinary feeding program. Readers should attend to the details of intervention protocols when interpreting the results of reviewed studies or attempting to replicate reported intervention methods.

Implications for Research

The results of this review cannot, and should not, be generalized to all children with feeding problems; more studies are needed to replicate and extend the interventions across different populations. Occupational therapy researchers need to perform more studies with rigorous designs that directly examine the effectiveness of specific techniques with specific populations. Future research efforts should focus on conducting research in children’s homes or natural settings to reflect the effectiveness of early intervention in those settings. For instance, most of the behavioral interventions in this review were conducted in the inpatient or outpatient setting with the efforts of multidisciplinary teams. As providers of early intervention, it is in occupational therapists’ interests to find out whether behavioral interventions using applied behavior analysis are effective in the home setting. Researchers should also investigate how best to incorporate parents or caregivers into treatment implementation and ascertain what training procedures or techniques are best for ensuring continued use after treatment has ended.

Limitations

This review raised three general concerns regarding the studies focusing on feeding intervention. First, we noted small sample sizes and limited sample representation in the studies included in the review. The average n for the total sample was 45, but the large standard deviation of 37 showed that the distribution of the sample size was skewed. Sample sizes in 10 of the 30 reviewed articles (excluding 4 systematic reviews) were <30. When small samples are used, power is substantially reduced (Portney & Watkins, 2000), and further justification is needed. None of the studies with small sample size (N < 30) provided evidence that they were powered sufficiently to demonstrate effects. The small sample sizes and representation of these studies limit their generalizability.

Second, limitations related to methods among the reviewed studies included lack of randomization, lack of sufficient detail in procedures, no identification of the most effective time frame or duration of intervention, lack of long-term follow-up, lack of comparison groups, and lack of specific treatment protocols. Without a description of the treatment protocol or detailed procedures, replicating the treatment and confirming the effectiveness of the reported intervention is difficult for clinicians and researchers. Our results echo those of Kerwin’s (1999) systematic review of behavior therapy that the reviewed studies provided little detail regarding when parents were introduced into the feeding sessions, how parents were trained, how (or if) they were instructed to fade the use of procedures, and their perspective on these procedures.

Third, several of the reviewed studies that have particular relevance to occupational therapists (i.e., that described specific techniques used in specific populations) had only Level III and Level IV evidence. The lack of objective outcome measures or rigorous study designs in Level III and Level IV studies may limit their generalizability.