PEDIATRIC PAIN SIG NEWSLETTER

Spring 2019

In this issue....

  1. Letter from the SIG Co-Chairs - by Sara Williams, PhD & Dustin Wallace, PhD

  2. International Research Spotlight: "Interoceptive exposure for children and adolescents with chronic pain: On the way, but not yet there" by Tanja Hechler, PhD

  3. Clinical Spotlight - "Acceptance and Commitment Therapy for Youth with Sickle Cell Disease: A Useful Approach" by Staci Martin, PhD

  4. SPPAC Spotlight- Pain-related programming to check out at the Society of Pediatric Psychology Annual Conference, April 4-6th in New Orleans!

Updates from the Pain SIG Co-Chairs!

We are pleased to share with you the Spring 2019 edition of Division 54's Pain SIG Newsletter! In our biannual letter, we aim to highlight important topics in pediatric pain, including research, clinical, and education activities, as well as update readers on what we've been up to in the Pain SIG.

First, we held our annual elections this winter and are thrilled to welcome four new members to our Board in the following positions:
  • Co-Chair: Karen Weiss
  • Education Committee Chair: Emily Wakefield
  • Research Committee Chair: Kelsey Borner
  • Student Representative: Kate Gamwell

They will join the continuing leaders:
  • Co-Chair: Sara Williams
  • Clinical Committee Chair: Rachael Coakley
  • Past Chair: Dustin Wallace

Special thanks to our outgoing board members: Staci Martin (Past Chair), Laura Simons (Research Committee Chair), Angela Fletcher (Education Committee Chair), and Melissa Pielech (Student Representative).

Second, we are gearing up for SPPAC 2019 in New Orleans! We will be hosting a Pain SIG meeting on Thursday April 4th from 4:30-5:45 pm at the conference venue. We welcome Pain SIG members and non-members of all professional and training levels to attend our meeting! You'll have an opportunity to meet the members of the Board, learn who are the winners of the poster awards, receive hot off the press data blitz presentations, and join the discussion of our committees on clinical, research, and education efforts. It's a wonderful opportunity to meet others working in the field of pediatric pain and gear up for all of the great pain related programming offered during the conference. Hope to see you there!

Third, we hosted another episode of our biannual webinar series in February. Dr. Lynn Waelde provided a talk on "Clinical Applications of Mindfulness in Pediatric Pain." We are pleased to report that the live webinar was well attended and well received! Those who missed it can access the talk on our website: https://ppainsig.weebly.com/education.html Also, we received helpful feedback from many attendees which will help us improve future webinars!

Finally, if you have an article you would like to contribute to a future edition, please contact our new Student Representative, Kate Gamwell (gamwell@ostatemail.okstate.edu), newsletter organizer extraordinaire. A special thanks to those who contributed to the current newsletter! Please enjoy the read!

Your 2018-2019 SIG co-chairs,
Dustin Wallace, Ph.D., and Sara Williams, Ph.D.

INTERNATIONAL RESEARCH SPOTLIGHT

Interoceptive exposure for children and adolescents with chronic pain: On the way, but not yet there

Tanja Hechler, PhD

Department of Clinical Psychology and Psychotherapy for Children and Adolescents, University of Trier, Germany

Contact details:

Prof. Dr. Tanja Hechler

Faculty of Psychology

Department of Clinical Psychology and Psychotherapy for Children and Adolescents

University of Trier, Germany

Email: hechler@uni-trier.de


Increased (pain-related) fear is associated with worsened treatment outcomes in children and adolescents with chronic pain, even when children undergo intensive interdisciplinary pain treatment (Hirschfeld, Hechler et al. 2013, Simons, Sieberg et al. 2018). Fear is the anticipatory emotional response to imminent threat, facilitating early and effective protection against future bodily threat or injury (Vlaeyen 2015, Vlaeyen, Crombez et al. 2016). Particularly interoceptive fear conditioning is hypothesized to be relevant for the acquisition of pain-related fear in individuals with chronic pain (De Peuter, Van Diest et al. 2011). In interoceptive fear conditioning, interoceptive stimuli (such as stomach grumbling) are repeatedly paired with an unconditioned stimulus (US; such as pain). Based on the contingency between the interoceptive stimulus and the US (pain), the interoceptive stimulus becomes a predictor of pain and will subsequently elicit a conditioned fear response. In line with these assumptions, we recently showed that adolescents with chronic abdominal pain (CAP, n = 20, 11-18 years) self-reported increased fear and avoidance when confronted with internal bodily sensations via muscle tension tasks (tightening abdominal muscles) in comparison to a safe comparison task (clench fists) (Flack, Pané-Farré et al. 2017). In a second sample of 34 adolescents with CAP and 50 adolescents with chronic headache, even the pure imagery of internal bodily sensations associated to the main pain resulted in a potentiation of the acoustic eye-blink startle response, a cranial-to-caudal spreading wave of flexor movements elicited by an abrupt sensory stimulus (Hechler, 2019, webinar IASP).


These findings are of clinical relevance. They suggest that adolescents with chronic pain react fearfully when they interpret interoceptive sensations as a warning signal for impeding pain. Such fear leads to avoidance behavior, which is defined as overt behavior preventing the occurrence of painful stimuli (Vlaeyen, Morley et al. 2016). Prolonged avoidance behavior is assumed to be critical for the development and persistence of chronic pain (Vlaeyen, Morley et al. 2016).


Interventions are thus warranted that are able to decrease the fear of internal bodily sensations, such as interoceptive exposure, the treatment of choice in anxiety research (Gerlach and Neudeck 2012). The rationale behind interoceptive exposure is that by repeated exposure to the feared internal bodily sensation and omitting avoidance and safety behavior, a reduction in the fear response will follow. More specifically, it is assumed that during interoceptive exposure the fear networks that are activated change as a result of inhibitory learning processes, resulting in reduced experienced fear when the individual is re-exposed to the bodily sensations (Weisman and Rodebaugh 2018). Even though the exact mechanisms are still under investigation, extinction learning is today considered an important mechanism (for a review, see (Urcelay 2012)). Henceforth, the interoceptive stimulus possesses both the excitatory meaning (i.e., fear-based, CS-US) as well as an inhibitory meaning (i.e., safety, CS – no US) with an increase in the inhibitory meaning following exposure (Weisman and Rodebaugh 2018).


To the best of our knowledge, only five studies have thus far investigated interoceptive exposure in children and adolescents with chronic pain (Hechler, Dobe et al. 2010, Allen, Tsao et al. 2012, Bonnert, Olen et al. 2017, Zucker, Mauro et al. 2017, Flack, Stahlschmidt et al. 2018). The studies vary considerably in the form of interoceptive exposure, the study aims, the age of the children and adolescents, the study design, the outcome variables, and the study results. Three studies implemented interoceptive exposure with symptom provocation tasks (Allen, Tsao et al. 2012, Bonnert, Olen et al. 2017, Zucker, Mauro et al. 2017). These tasks ranged from spinning while standing, a task from the audio-vestibular domain, to running down the hall with a belt fastened around the belly, a disorder-specific task. Two studies used interoceptive exposure in sensu and instructed the adolescents to imagine increases in pain intensity by focusing on related thoughts, memories, emotions and bodily sensations (Hechler, Dobe et al. 2010, Flack, Stahlschmidt et al. 2018).


Results of the five studies can be summarized as follows: In our own study, we found a greater decrease in pain intensity and school aversion in the group of adolescents who received interoceptive exposure in sensu on top of intensive interdisciplinary pain treatment (Hechler, Dobe et al. 2010). Flack et al. (2018) found in a randomized-controlled trial (RCT) large significant reductions in fear of pain in both groups, the group that received interoceptive exposure in sensu and intensive pain treatment and the group that received relaxation and intensive pain treatment. They also found that adolescents with initial high fear of pain showed greater decreases in fear of pain when they belonged to the interoceptive exposure group. Allen et al. (2012) aimed to describe a unified, trans-diagnostic treatment for adolescents with chronic pain and comorbid anxiety and depression. Module four included situational exposures, e.g. interoceptive exposure. They report decreases in anxiety, fear of pain and pain-related disability in a case of a 14-year old boy. Zucker et al. (2017) developed an acceptance-based interoceptive exposure with symptom provocation tasks for young children with abdominal pain (5-9 years). Their treatment was designed to promote a playful and curious approach towards internal bodily signals, to provide caregivers and children help to describe, label and interpret the meaning of internal signals, and to employ strategies that attempt to respond to internal bodily sensations and to notice how the body changes. Pain and negative affect both demonstrated clinically meaningful and statistically significant changes in their study after the intervention. Bonnert et al. (2017) compared global gastrointestinal symptoms in a RCT in a group that received an internet-cognitive behavior treatment including interoceptive exposure with symptom provocation tasks and a waiting-list control group. Results revealed significantly larger pre- to posttreatment group changes in gastrointestinal symptoms in the interoceptive exposure group compared to the control group.


Research into interoceptive exposure in children and adolescents with chronic pain is clearly on its way, and results are promising. However, we are not there yet. Prior to be able to provide clinical recommendations, open questions need to be addressed in future studies. Questions such as the following:


How to design symptom provocation tasks? The symptom provocation tasks implemented in the studies by Allen et al. (2012), Zucker et al. (2017) and Bonnert et al. (2017) vary considerably. Symptom provocation tasks should elicit a comprehensive fear response in children and adolescents with chronic pain (Neudeck, im Brahm et al. 2018). However, no study has yet explored if the tasks used in the existing forms of interoceptive exposure are capable of eliciting comprehensive fear responses.


How to design interoceptive exposure in sensu? The interoceptive exposure in sensu in the two studies by Hechler et al. (2010) and Flack et al. (2018) require adolescents to imagine an increase in their pain intensity. The increase in pain intensity was accomplished by instructing the adolescents to focus on related thoughts, memories, emotions and bodily sensations (Flack, Stahlschmidt et al. 2018). The instructions are highly heterogeneous. No study has yet investigated whether and which of these instructions are capable to elicit a comprehensive fear response.


Which form of interoceptive exposure is better, symptom provocation tasks or in sensu? No study has yet compared the two forms of interoceptive exposure – symptom provocation tasks, in sensu– in children and adolescents with chronic pain. This comparison allows drawing conclusions on which form of interoceptive exposure may be most suitable to decrease fear of internal bodily sensations.


Which outcome variables should be assessed? The studies vary considerably in their core outcome variables, ranging from retrospectively assessed average pain intensity (Hechler, Dobe et al. 2010) to retrospective survey methods such fear of pain questionnaires (Flack, Stahlschmidt et al. 2018). Retrospective surveys have profound disadvantages such as asking children to reflect back on symptoms during a defined time period. Momentary data collection strategies that ask participants to provide self-report ratings of their current fear of internal bodily sensations during various times a day have significant advantages (Wen, Schneider et al. 2017): they reduce the recall bias of retrospective survey methods. They can be collected in the natural setting of the adolescents, and they allow for an examination of variations in fear across time and across individuals. Despite these advantages, momentary data collection strategies are still scarce in pain research with children and adolescents (Connelly and Bickel 2011, Bromberg, Connelly et al. 2016) and have not yet been implemented in interoceptive exposure studies.


Which changes occur in individual children and adolescents following interoceptive exposure? Each of the five studies focused on group comparisons. Interoceptive exposure in chronic pain research is, however, still in a developmental phase. An investigation of individual changes throughout and following the sessions of interoceptive exposure as a proof-of-concept trial is therefore warranted. This investigation can only be done when focusing on momentary and repeated assessment of core outcomes in individual cases who undergo researcher-controlled phases of interoceptive exposure in comparison to phases without the intervention, as can be done within single-case experimental designs (SCED) (Cohen, Feinstein et al. 2013).

Given the clinical relevance of fear of internal bodily sensations in children and adolescents with chronic pain, it is essential to address the above-mentioned research questions. Only, if we increase our knowledge in this area will we be able to provide clinical recommendations for use of interoceptive exposure in children and adolescents with chronic pain.

CLINICAL SPOTLIGHT

Acceptance and Commitment Therapy for Youth with Sickle Cell Disease: A Useful Approach

Staci Martin, PhD

Health Psychology and Neurobehavioral Research Group, National Cancer Institute, NIH


Contact details:

Dr. Staci Martin

Licensed Psychologist

Senior Associate Scientist

Behavioral Health Core
Clinical & Training Director, Health Psychology and Neurobehavioral Research Group
National Cancer Institute, National Institutes of Health, Bethesda, MD

martins@MAIL.NIH.GOV


Health Psychology and Neurobehavioral Research Group, National Cancer Institute, NIH

Pain is one of the hallmark symptoms of sickle cell disease (SCD). There are multiple causes of pain in youth with SCD, with the most common being sickle-shaped blood cells blocking blood flow. The pain experience can include both recurrent, acute episodes (“pain crises”) and a more chronic pain syndrome involving daily pain. While children with SCD can begin having pain crises in the first year of life, the addition of chronic pain often accompanies the transition into adolescence and emerging adulthood (Smith & Scherer, 2010). The impact that SCD pain can have on children and adolescents’ quality of life is far-reaching, and relates to factors such as school absences, medication side effects, depression, anxiety, and loss of identity. In addition, adolescents and their caregivers have reported feeling stigmatized across medical and community settings (Wesley, Zhao, Carroll, & Porter, 2016).Thus, the role of the pediatric psychologist is central to supporting the healthy development of affected youth.


Acceptance and Commitment Therapy (ACT) is a treatment model that has been useful and effective when applied to youth with pain, including SCD-related pain. The goal of ACT is to increase psychological flexibility, a construct associated with overall wellbeing(Kashdan & Rottenberg, 2010). The core concepts in ACT include present-moment awareness (or mindfulness), defusion (getting distance from difficult thoughts and feelings), self-as-context (which involves perspective taking), acceptance, valued-based living, and committed action. Each of these constructs plays an important part in treatment plans for youth with SCD.


During a pain crisis, patients may be resistant to the idea of learning to do mindful breathing. It is ideal to teach this skill ahead of time so that they are familiar with the processes and may be less overwhelmed when in moderate to severe pain. In addition, use of a smartphone application (e.g., Stop, Breathe, and Think; Headspace) can provide a way for patients to listen to audio-guided meditations without having to engage with the therapist. Mindful body scans can be very useful for kids and adolescents with chronic pain. These are different from progressive muscle relaxation exercises, since the aim is not to increase relaxation (although this often occurs). Rather, the goal is to engender one’s ability to notice painful sensations without impulsively responding. With repetition, gradual acceptance of pain occurs such that less energy is spent on trying to control or get rid of pain, which is often a futile endeavor in SCD.


In recent years, increasing attention has been paid to the concept of illness Identity, or the extent to which a chronic illness is integrated into one’s overall sense of self (e.g. (Luyckx et al., 2018; Oris et al., 2016). During adolescence and young adulthood, identity exploration and establishment are naturally occurring. For youth with SCD, this process can be disrupted, since adolescence is a time when pain crises may increase in frequency, pain becomes more chronic, and hospitalizations may become more common. In effect, so much of the adolescent’s focus and energy is on controlling their disease that they can lose sight of other aspects of their lives. From an ACT perspective, there is the danger of the self being viewed as content (“sickle cell patient”) rather than in context. In working with these youth, it is helpful to guide them towards exploring their values. This can be done by asking questions such as “Who are the people that are most important to you?”, “What things or activities matter the most?”, and “What do you want your life to stand for?” While adolescents may think about these questions differently than adults, it is still important to explore so that their pain can occur in the context of valued living.


Another challenge encountered by youth with SCD is that of being stigmatized by healthcare professionals (who may see them as drug-seeking), by schools, and even by unaffected family members, who may express skepticism at the patient’s pain and question if they are “faking it” for secondary gains. Simply validating these patients’ pain experience is a good place to start, as this lays the groundwork for acceptance. Connecting teens with other SCD youth, through individual contacts or in-person or online support groups, can be useful as well, since the patient can begin to view his or her situation from a broader, more accepting perspective. Finally, it is important to explore the extent to which the patient has internalized harmful attributions (e.g., “My pain isn’t important” or “I should be able to control my pain better”) and help them to gently defuse from these beliefs.


While existing research on ACT for pain strongly supports its efficacy with a wide variety of pain conditions, randomized trials comparing ACT with other treatments among youth with SCD are needed. Nevertheless, the ACT model offers a very useful framework for increasing psychological flexibility and optimizing quality of life among young patients with SCD living with acute and/or chronic pain.

SPPAC SPOTLIGHT: PAIN-RELATED HAPPENINGS

If we accidentally missed highlighting your pain-relevant presentation, please accept our apologies & email Melissa so that we can update the newsletter :) mpielech@unm.edu


Thursday April 4th

4:30-5:45 pm: Pain SIG meeting (Riverview 2)- See you there!


Friday April 5th

2:15-3:30pm

Symposium: Peer Mentoring Interventions for Adolescents and Young Adults with Chronic Illness – Galerie 5

Chair: Adrienne Viola, MPH Discussant: Sara Ahola Kohut, PhD

  • The iPeer2Peer Program: Online Peer Mentoring for Youth with Juvenile Idiopathic Arthritis Sara Ahola Kohut, PhD
  • The Development of a Medical Student Mentor Intervention to Improve Transition Outcomes in Young Adults with Sickle Cell Disease Adrienne Viola, MPH


Symposium: Outstanding Research by Students and Trainees – Galerie 6

Chair/Discussant: Jessica Fales, PhD

  • Daily Associations Among Peer Victimization, Mood, Sleep, Pain, and Disability Lexa Murphy, PhD, Jessica Fales, PhD, & Tonya Palermo, PhD
  • Self-Management Intervention Improves Behavioral Activation in Adolescents and Young Adults with Sickle Cell Disease Anna Hood PhD, Cara Nwankwo BA, Katie Kidwell PhD, Naomi Joffe PhD, Emily McTate PhD and Lori Crosby PsyD


Professional Development: The Role of Pediatric Psychologists in Consulting to Colleagues on Behavior Management within Interdisciplinary Healthcare Programs – Bissonet Deirdre Logan, PhD, Gerard Banez, PhD, Nancy Bandstra, PhD, and Healther Molind, DPT


3:45-4:45 pm

PLENARY ADDRESS: Building Resilience to Chronic Pain and Distress by Improving Behavioral Flexibility in Children and Parents Speaker: Rikard K. Wicksell, PhD


5:00-6:15pm

Symposium: The Impact of Social Rejection: Navigating Health-Related Stigma in Pediatric Chronic Illness – Galerie 4

Chair: Sarah R. Martin, PhD Discussant: Emily O. Wakefield, PhD

  • “Please Believe I Have Pain:” How the Invisibility of Pain Symptoms Leads to Stigma in Adolescents with Chronic Pain Emily O. Wakefield, PsyD, William T. Zempsky, MD, Mark Litt, PhD, & Rebecca Puhl, PhD
  • A Closer Look at Health-Related Stigma in Adolescents with Sickle Cell Disease Sarah R. Martin, PhD, Ifigenia Mougianis, PhD, & Lindsey L. Cohen, PhD


Saturday April 6th

10:30-11:45am

Symposium: Sleep and Pain: Using Research to Inform Clinical Practice in Youth with Pain to Promote Resilience – Galerie 5

Chair: Sara E. Williams, PhD Discussant: Ethan Benore, PhD

  • Improvements in Sleep Relate to Improvements in Pain Among Youth Undergoing Inpatient Chronic Pain Rehabilitation Sara E. Williams, PhD
  • Importance of Sleep in Youth with Acute Pain: Identifying Risk Factors for Poor Outcomes in the Post-injury Period Amy Holley, PhD
  • Good Sleep Patterns Promote Resilience for Healthcare Use in Response to Pain in Youth with Sickle Cell Disease Cecelia Valrie, PhD
  • Practical Application: Treating Risk Factors and Building Resilience Related to Sleep Among Youth with Chronic Pain Ethan Benore, PhD


Symposium: From Screening to Follow Up – Galerie 6

Chairs: Cynthia Karlson, PhD & Kevin Tsand, PsyD Discussant: Jordan Gilleland Marchak, PhD

  • Referral Outcomes from a Neurocognitive Screening Program for Pediatric Sickle Cell Disease Jeffrey Karst, PhD, Meghan Miller, MA, J Paul Scott, MD, Jenny Hoag, PhD, & Kristin Bingen, PhD


1:15-2:30pm

Symposium: Applications of Technological Tools Across Multiple Pediatric Populations: Lessons Learned and Future Directions for Implementation – Galerie 5

Chair/Discussant: Idia Thurston, PhD

  • Using Technology to Understand the Daily Relationship Between Pain and Weight Melissa Santos, PhD, Madison Bracken, MA, Alan Ahlberg, MA, Amy Gorin, PhD & William Zempsky, MD


Symposium: Real Pain? Patterns and Clinical Implications of Provider Pain Dismissal in Adolescents and Emerging Adults – Galerie 6

Chair: W. Hobart Davies, PhD Discussant: Deirdre Logan, PhD

  • Common Patterns of Pain Dismissal Among Typically Developing Adolescents and Emerging Adults Ellen Sejkora, MS
  • Gender Differences in the Experience and Perception of Pain Dismissal in Adolescence and Emerging Adulthood Eva Igler, MA & W. Hobart Davies, PhD
  • Clinical Implications of Pain Dismissal: Using a Biopsychosocial Framework to Restore Patients’ Trust and Improve Patient-provider Interactions Chasity Brimeyer, PhD


2:45-4:00pm

Symposium: Neuroimaging in Pediatric Psychology Research: Mechanisms and Intervention Targets – Galerie 6 Chair: Matthew Hocking, PhD Discussant: Laura Simons, PhD

  • Interplay of Fear and Pain Circuitry in Pediatric Pain Laura Simons PhD, Lauren Heathcote PhD, Inge Timmers PhD, Christian Soares, & David Borsook MD,PhD


& don't forget about all of the amazing pain-related POSTERS!

REFERENCES

Allen, L. B., et al. (2012). "A Unified, Transdiagnostic Treatment for Adolescents With Chronic Pain and Comorbid Anxiety and Depression." Cogn Behav Pract 19(1): 56-67.


Bonnert, M., et al. (2017). "Internet-Delivered Cognitive Behavior Therapy for Adolescents With Irritable Bowel Syndrome: A Randomized Controlled Trial." Am J Gastroenterol 112(1): 152-162.


Bromberg, M. H., et al. (2016). "Prospective Mediation Models of Sleep, Pain, and Daily Function in Children With Arthritis Using Ecological Momentary Assessment." Clinical Journal of Pain 32(6): 471-477.


Cohen, L. L., et al. (2013). "Single-case research design in pediatric psychology: Considerations regarding data analysis." Journal Pediatr Psychol 39(2): 124-137.


Connelly, M. and J. Bickel (2011). "An electronic daily diary process study of stress and health behavior triggers of primary headaches in children." J Pediatr Psychol 36(8): 852-862.


De Peuter, S., et al. (2011). "Understanding fear of pain in chronic pain: interoceptive fear conditioning as a novel approach." European Journal of Pain 15(9): 889-894.


Flack, F., et al. (2017). "Do Interoceptive Sensations Provoke Fearful Responses in Adolescents With Chronic Headache or Chronic Abdominal Pain? A Preliminary Experimental Study." Journal Pediatr Psychol 42(6): 667-678.


Flack, F., et al. (2018). "Efficacy of adding interoceptive exposure to intensive interdisciplinary treatment for adolescents with chronic pain: A randomized controlled trial." Pain 159(11): 2223-2233.


Gerlach, A. L. and P. Neudeck (2012). Interoceptive exposure. Exposure Therapy, Springer: 183-196.


Hechler, T., et al. (2010). "The pain provocation technique for adolescents with chronic pain: preliminary evidence for its effectiveness." Pain Med 11(6): 897-910.


Hirschfeld, G., et al. (2013). "Maintaining lasting improvements: one-year follow-up of children with severe chronic pain undergoing multimodal inpatient treatment." Journal Pediatr Psychol 38(2): 224-236.


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Luyckx K, Oris L, Raymaekers K, Rassart J, Moons P, Verdyck L, Mijnster T, Mark RE: Illness identity in young adults with refractory epilepsy. Epilepsy Behav 80:48–55, 2018.


Neudeck, P., et al. (2018). "Transdiagnostische expositionsbasierte Behandlung von Angststörungen." Zeitschrift für Klinische Psychologie und Psychotherapie.


Oris L, Rassart J, Prikken S, Verschueren M, Goubert L, Moons P, Berg CA, Weets I, Luyckx K: Illness Identity in Adolescents and Emerging Adults With Type 1 Diabetes: Introducing the Illness Identity Questionnaire. Diabetes Care 39:757–63, 2016.


Simons, L. E., et al. (2018). "Children With Chronic Pain: Response Trajectories After Intensive Pain Rehabilitation Treatment." Journal of Pain 19(2): 207-218.


Smith WR, Scherer M: Sickle-Cell Pain: Advances in Epidemiology and Etiology. Hematology

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Urcelay, G. P. (2012). Exposure techniques: The role of extinction learning. Exposure Therapy, Springer: 35-63.


Vlaeyen, J. W. (2015). "Learning to predict and control harmful events: chronic pain and conditioning." Pain 156 Suppl 1: S86-93.


Vlaeyen, J. W., et al. (2016). "The fear-avoidance model of pain." Pain 157(8): 1588-1589.


Vlaeyen, J. W., et al. (2016). "The experimental analysis of the interruptive, interfering, and identity-distorting effects of chronic pain." Behav Res Ther 86: 23-34.


Weisman, J. S. and T. L. Rodebaugh (2018). "Exposure therapy augmentation: A review and extension of techniques informed by an inhibitory learning approach." Clin Psychol Rev 59: 41-51.


Wen, C. K. F., et al. (2017). "Compliance With Mobile Ecological Momentary Assessment Protocols in Children and Adolescents: A Systematic Review and Meta-Analysis." J Med Internet Res 19(4): e132.


Wesley KM, Zhao M, Carroll Y, Porter JS: Caregiver Perspectives of Stigma Associated With Sickle Cell Disease in Adolescents. J Pediatr Nurs 31:55–63, 2016.


Zucker, N., et al. (2017). "Acceptance-based interoceptive exposure for young children with functional abdominal pain." Behav Res Ther 97: 200-212.