3.1 Impact of timing of referral or treatment on outcomes
A Cochrane review of psychological interventions used in chronic pain found 37 moderate to low quality randomised controlled trials ( RCTs). There were no studies identified assessing the effect of the timing of interventions. Site of therapy delivery varied and included clinic (18 studies), home (including internet or computer-based) and school (3 studies). Some benefit was found in treatment delivered in schools [16-18].
Another comprehensive review, without critical appraisal of the literature, did look at tools of early identification of development of chronic pain, but did not examine the effect of timing of intervention .
A RCT of 321 children aged 8 – 18 years, attending a hospital pain service were administered a Paediatric Pain Screening Tool ( PPST). The PPST was adapted from the StartBack screening tool with the goal of identifying children with higher risk of adverse outcomes, and potentially facilitating targeted treatment . The risk groups, as assigned by the PPST, were not affected by pain diagnosis, site, or duration. Of participants displaying high levels of disability and distress at 4 month follow up, only 2-7% had been identified as low risk at baseline assessment.
There is moderate evidence that early-intervention psychological therapy could have a modest impact on pain and disability, but no evidence of an effect on depression or anxiety .
There is a lack of good quality evidence that the timing of intervention affects outcomes for chronic pain management in children and young people.
There is also moderate evidence of a potentially predictive screening tool to stratify risk.
- Use of a screening tool to identify children and young people at risk of adverse outcomes, due to chronic pain, should be considered to aid in planning intensity and type of intervention.
- Early biopsychosocial assessment and psychological intervention should be considered, particularly where the risk of disability and distress is high.
3.2 Nature of interaction with healthcare professionals, education system and parents
Expert clinical opinion would support the hypothesis that clinical outcomes for children and young people with chronic pain are mediated, at least in part, by their interactions with others, both in a clinical and a social context. Pain in turn influences cognitive and social functioning and may negatively impact upon interactions with family members, school and peers . Commissioning services in England and Wales have recognised the importance of multidisciplinary input for management of chronic pain in children and young people, although the nature of the interactions have not been defined .
A good quality systematic review found that intensive interdisciplinary management (typically delivered in an inpatient or hospital setting, on average 8 hours of treatment a day) had a positive effect on clinical outcomes: while demonstrating significant heterogeneity, in general, at post-treatment there were large improvements for disability, small to moderate improvements for pain intensity and small to moderate improvements for depressive symptoms. Positive effects were maintained at short-term follow-up, including improvement in school functioning. The specific effect of interactions with HCPs, education and parents were not explored .
A systematic review identified a beneficial effect for online interventions, however the number of studies were small. A meta-analysis of available data found a modest pooled effect size (-0.41 [range 0.17--0.55]) for reductions in pain intensity after computerised CBT, with a mean odds ratio of 6.03 [confidence interval 2.67, 13.63] for significant reductions in pain intensity compared to control .
A comprehensive systematic review of parental influences on functional abdominal pain ( FAP) could not establish a clear relationship due to an insufficient number of good quality studies. There was some increase in reporting of physical symptoms in parents of children with FAP (effect size d=0.36) compared to parents of typically healthy children .
A narrative review has described emerging evidence suggesting a bidirectional relationship between chronic pain in children and family functioning, e.g. conflict and cohesion. The authors commented that interpreting individual studies is difficult due to the lack of longitudinal data. Children’s and parental responses to pain may change over time and responses may vary depending on the developmental stage when the pain first began. Following on from this, it is unclear if the efficacy of interventions aimed at parental responses to children’s pain is modified by the duration of pain and developmental stage 
Non-verbal children, or children with communication difficulties, are at even greater risk of under-treated pain as carers and clinicians may be unaware of the existence of validated pain assessment tools, such as the FLACC (Faces, Legs, Activity, Cry, and Consolability) and the Paediatric Pain Profile. There is a deficiency in knowledge translation and the implementation of research findings in clinical practice [27, 28].
- The potential effects (both positive and negative) of children’s interactions with family, clinicians, educators and peers on assessment and management of chronic pain should be considered. Regarding the nature of interactions with healthcare providers and clinical interventions, remote or online delivery may be considered as an alternative to face to face.