Rates and predictors of visits to primary care physicians during and after treatment of childhood acute lymphoblastic leukemia: A population-based cohort study.

INTRODUCTION: Patient re-engagement with primary care physicians (PCPs) after cancer treatment is essential to facilitate survivorship care and to meet non-oncology primary care needs. We identified rates and predictors of PCP visits both during and after treatment among a population-based cohort of children with acute lymphoblastic leukemia (ALL). METHODS: Children of age less than 18 years at ALL diagnosis in Ontario between 2002 and 2012 were linked to administrative data and matched to controls without cancer. PCPs at diagnosis were identified and PCP visit rates during treatment compared between patients and controls. Post-treatment PCP visit rates were also calculated. Predictors included demographic-, disease-, and PCP-related variables. RESULTS: A total of 743/793 (94%) patients and 3112/3947 (79%) controls had a PCP at diagnosis. Almost half of patients (361/743, 45%) did not visit their PCP during treatment. Visit rate during treatment was 0.64 per person per year (PPPY) versus 1.4 PPPY among controls (adjusted rate ratio [aRR] 0.47, 95th confidence interval [95CI]: 0.40-0.54; p < .0001). No disease- or PCP-related factors were associated with visit rates. Total 711 patients completed frontline therapy; 287 (40.4%) did not have a PCP visit after treatment. Nonetheless, survivors overall visited PCPs post treatment more often than controls (aRR 1.4, 95CI: 1.2-1.6; p < .0001). Survivors who saw their PCP during treatment had post-treatment visit rates twice that of other survivors (aRR 2.0, 95CI: 1.6-2.5; p < .0001). CONCLUSIONS: Only a portion of children with ALL see their PCPs during treatment and return to PCP care following treatment completion. Post-treatment engagement with PCPs may be improved by PCP involvement during ALL treatment.

Pediatric refractory immune thrombocytopenia: A systematic review.

Pediatric immune thrombocytopenia (ITP) is an acquired disorder associated with autoimmune destruction and impairment of platelet production in children. Some children exhibit poor or transient response to ITP-directed treatments and are referred to as having refractory ITP (rITP). There is currently no consensus on the definition of rITP, nor evidence-based treatment guidelines for patients with rITP. After a survey of pediatric ITP experts demonstrated lack of consensus on pediatric rITP, we pursued a systematic review to examine the reported clinical phenotypes and treatment outcomes in pediatric rITP. The search identified 253 relevant manuscripts; following review, 11 studies proposed a definition for pediatric rITP with no consensus amongst them. Most definitions included suboptimal response to medical management, while some outlined specific platelet thresholds to define this suboptimal response. Common attributes identified in this study should be used to propose a comprehensive definition, which will facilitate outcome comparisons of future rITP studies.

Generic Health-Related Quality of Life Utility Measure for Preschool Children (Health Utilities Preschool): Design, Development, and Properties.

OBJECTIVES: Health Utilities Preschool (HuPS) was developed to fill the need for a generic preference-based measure (GPM) applicable in early childhood. A GPM has all the properties for higher-order summary measures, such as quality-adjusted life-years, required to inform important policy decisions regarding health and healthcare services. METHODS: Development was in accordance with published standards for a GPM, statistical procedures, and modeling. HuPS incorporates key components of 2 existing measurement systems: Health Status Classification System for Preschool Children and Health Utilities Index Mark 3 (HUI3). The study included a series of 4 measurement surveys: definitional, adaptational, quantificational, and evaluational health-related quality of life (HRQL). HuPS measurements were evaluated for reliability, validity, interpretability, and acceptability. RESULTS: Definitional measurements identified 8 Health Status Classification System for Preschool Children attributes in common with HUI3 (vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain and discomfort), making the HUI3 scoring equation commensurate with HuPS health states. Adaptational measurements informed the content of attribute-level descriptions (n = 35). Quantificational measurements determined level scoring coefficients. HRQL scoring inter-rater reliability (intraclass correlation coefficient = 0.79) was excellent. Continuity of HRQL scoring with HUI3 was reliable (intraclass correlation coefficient = 0.80, P < .001) and valid (mean absolute difference = 0.016, P = .396). CONCLUSIONS: HuPS is an acceptable, reliable, and valid GPM. HRQL scoring is continuous with HUI3. Continuity expands the applicability of GPM (HUI3) scoring to include subjects as young as 2 years of age. Widespread applications of HuPS would inform important health policy and management decisions as HUI3 does for older subjects.

Healthcare utilization and costs associated with acute lymphoblastic leukemia in children with and without Down syndrome.

BACKGROUND: Children with Down syndrome (DS) and acute lymphoblastic leukemia (ALL) are at increased risk of treatment-related morbidity and mortality compared to non-DS-ALL, requiring increased supportive care. We examined the healthcare utilization and costs in DS-ALL patients to inform future evaluations of novel therapies. METHODS: A provincial registry identified all children (1-17 years) diagnosed with B-lineage ALL in Ontario, Canada between 2002 and 2012. Detailed demographic, disease, treatment, and outcome data were abstracted. Linkage to population-based health services databases identified all outpatient and emergency department (ED) visits, hospitalizations, and physician billings. Healthcare utilization costs were available for patients diagnosed during 2006-2012 using validated algorithms (2018 Canadian dollars). Healthcare utilization rates and costs were compared between DS and non-DS patients using regression models, adjusting for all covariates. RESULTS: Of 711 patients, 28 (3.9%) had DS. Adjusting for all covariates, children with DS-ALL experienced substantially higher rates of ED visits (rate ratio [RR] 1.5, 95% confidence interval [95% CI]: 1.2-2.0; p = .001) and inpatient days (RR 2.5, 95% CI: 1.4-4.5; p = .002) compared to non-DS children. Outpatient visit rates were similar (RR 1.1, 95% CI: 0.9-1.3; p = .41). Among patients with available cost data (N = 533, DS = 19), median 5-year healthcare utilization cost was $247,700 among DS patients (interquartile range [IQR]: 200,900-354,500) and $196,200 among non-DS patients (IQR: 148,900-280,300; p = .02). In adjusted analyses, DS-associated costs were 50% higher (RR 1.5, 95% CI: 1.2-1.9; p < .002). CONCLUSIONS: Healthcare utilization and treatment costs of DS-ALL patients are substantially higher than those of non-DS-ALL. Our data provide a baseline for future DS-specific cost-effectiveness studies.

A Pilot Randomized Control Trial of Teens Taking Charge: A Web-based Self-management Program for Adolescents with Cancer.

Background: There is a lack of self-management tools for adolescents with cancer (AWC). This study evaluated the feasibility of Teens Taking Charge Cancer, a web-based self-management program. Methods: A pilot randomized control trial (RCT) was conducted across 4 pediatric oncology clinics. AWC (12-18 years) and their caregivers were randomized to either the intervention or control group. All were asked to complete 12 website modules over 12 weeks (at their own pace) and received monthly calls from health coaches. The intervention website was based on cognitive behavioral principals, designed as an interactive self-guided online program, while the control consisted of education and included links to 12 general cancer websites. Outcome assessments occurred at enrollment and 12 weeks post-intervention. The primary outcomes included rate of accrual and retention, adherence to the protocol, acceptability and satisfaction with intervention using questionnaire and semi-structured interviews, adverse events and engagement with the intervention. Results: Eighty-one teen-caregiver dyads were enrolled with a retention rate of 33%. In the intervention group 46% (n = 18) logged in at least once over the 12-week period. A mean of 2.4 of 12 modules (SD 3.0) were completed; and no one completed the program. Thirty-three percent of caregivers in the intervention logged into the website at least once and none completed the full program. Discussion: The results from this pilot study suggest that the current design of the Teens Taking Charge Cancer RCT lacks feasiblity. Future web-based interventions for this group should include additional features to promote uptake and engagement with the program.

Health-related quality of life and fatigue in children and adults with pyruvate kinase deficiency.

Pyruvate kinase deficiency (PKD) is the most common cause of congenital nonspherocytic hemolytic anemia. Although recognition of the disease spectrum has recently expanded, data describing its impact on health-related quality of life (HRQoL) are limited. In this prospective international cohort of 254 patients (131 adults and 123 children) with PKD, we used validated measures to assess the impact of disease on HRQoL (EuroQol 5-Dimension Questionnaire, Pediatric Quality of Life Inventory Generic Core Scale version 4.0, and Functional Assessment of Cancer Therapy-Anemia) and fatigue (Patient Reported Outcomes Measurement Information System Fatigue and Pediatric Functional Assessment of Chronic Illness Therapy-Fatigue). Significant variability in HRQoL and fatigue was reported for adults and children, although individual scores were stable over a 2-year interval. Although adults who were regularly transfused reported worse HRQoL and fatigue compared with those who were not (EuroQol-visual analog scale, 58 vs 80; P = .01), this difference was not seen in children. Regularly transfused adults reported lower physical, emotional, and functional well-being and more anemia symptoms. HRQoL and fatigue significantly differed in children by genotype, with the worst scores in those with 2 severe PKLR mutations; this difference was not seen in adults. However, iron chelation was associated with significantly worse HRQoL scores in children and adults. Pulmonary hypertension was also associated with significantly worse HRQoL. Additionally, 59% of adults and 35% of children reported that their jaundice upset them, identifying this as an important symptom for consideration. Although current treatments for PKD are limited to supportive care, new therapies are in clinical trials. Understanding the impact of PKD on HRQoL is important to assess the utility of these treatments. This trial was registered at www.clinicaltrials.gov as #NCT02053480.

Poor outcome after hematopoietic stem cell transplantation of patients with unclassified inherited bone marrow failure syndromes.

Classification of inherited bone marrow failure syndromes (IBMFSs) according to clinical and genetic diagnoses enables proper adjustment of treatment. Unfortunately, 30% of patients enrolled in the Canadian Inherited Marrow Failure Registry (CIMFR) with features suggesting hereditability could not be classified with a specific syndromic diagnosis. We analyzed the outcome of hematopoietic stem cell transplantation (HSCT) in unclassified IBMFSs (uIBMFSs) and the factors associated with outcome. Twenty-two patients with uIBMFSs and 70 patients with classified IBMFSs underwent HSCT. Five-year overall survival of uIBMFS patients after HSCT was inferior to that of patients with classified IBMFSs (56% vs 76.5%). The outcome of patients with uIBMFS who received cord blood was significantly lower than that of patients who received other stem cell sources (14.8% vs 90.9%). Engraftment failure was higher among patients with uIBMFS who received cord blood than those who received bone marrow. None of the following factors were significantly associated with poor survival: transfusion load, transplant indication, the intensity of conditioning regimen, human leukocyte antigen-identical sibling/alternative donor. We suggest that identifying the genetic diagnosis is essential to modulate the transplant procedure including conditioning agents and stem cell sources for better outcome and the standard cord blood transplantation (CBT) should be avoided in uIBMFS.

Pyruvate kinase deficiency in children.

BACKGROUND: Pyruvate kinase deficiency (PKD) is a rare, autosomal recessive red blood cell enzyme disorder, which leads to lifelong hemolytic anemia and associated complications from the disease and its management. METHODS: An international, multicenter registry enrolled 124 individuals younger than 18 years old with molecularly confirmed PKD from 29 centers. Retrospective and prospective clinical data were collected. RESULTS: There was a wide range in the age at diagnosis from 0 to 16 years. Presentation in the newborn period ranged from asymptomatic to neonatal jaundice to fulminant presentations of fetal distress, myocardial depression, and/or liver failure. Children <5 years old were significantly more likely to be transfused than children >12 to <18 years (53% vs. 14%, p = .0006), which correlated with the timing of splenectomy. Regular transfusions were most common in children with two severe PKLR variants. In regularly transfused children, the nadir hemoglobin goal varied considerably. Impact on quality of life was a common reason for treatment with regular blood transfusions and splenectomy. Splenectomy increased the hemoglobin and decreased transfusion burden in most children but was associated with infection or sepsis (12%) and thrombosis (1.3%) even during childhood. Complication rates were high, including iron overload (48%), perinatal complications (31%), and gallstones (20%). CONCLUSIONS: There is a high burden of disease in children with PKD, with wide practice variation in monitoring and treatment. Clinicians must recognize the spectrum of the manifestations of PKD for early diagnostic testing, close monitoring, and management to avoid serious complications in childhood.

Phase-specific risks of outpatient visits, emergency visits, and hospitalizations during Children's Oncology Group-based treatment for childhood acute lymphoblastic leukemia: A population-based study.

BACKGROUND: Therapy for childhood acute lymphoblastic leukemia (ALL) is associated with substantial health care utilization and burden on families. Little is known about health care utilization during specific treatment phases. PROCEDURES: We identified children with ALL diagnosed during 2002-2012 in Ontario, Canada and treated according to Children's Oncology Group (COG) protocols. Disease and treatment data were chart abstracted. Population-based health care databases identified all outpatient visits, emergency department (ED) visits, and hospitalizations. In addition to comparing standard and intensified versions of treatment phases, we compared patients receiving different steroids (dexamethasone vs. prednisone) and different versions of interim maintenance (IM) (Capizzi vs. high-dose methotrexate [HD-MTX]). RESULTS: Six hundred thirty-seven children met inclusion criteria. During intensified consolidation, 76.2% of patients were hospitalized at least once, compared to only 32.3% of patients receiving standard consolidation (p < .0001). Similarly, 72.9% of patients receiving intensified delayed intensification (DI) were hospitalized during this phase compared to 50.3% of patients receiving standard DI (p < .0001). Among patients receiving a four-drug induction, those receiving dexamethasone had an 85% higher rate of ED visits (adjusted rate ratio [aRR] 1.85, 95th confidence interval [95CI] 1.14-3.00; p = .01) and a 44% higher rate of hospitalization (aRR 1.44, 95CI 1.24-1.68) compared to those receiving prednisone. Among high-risk B-ALL and T-ALL patients in IM, Capizzi MTX was not associated with an increased rate of ED visits versus HD-MTX. CONCLUSIONS: These results can be used to inform anticipatory guidance for families, particularly those undergoing intensified therapy. Our results also suggest that increased toxicity rates associated with dexamethasone during Induction seen in clinical trials reflect real-world practice.

Clinical and Demographic Factors Associated with Distress in Adolescent and Young Adults with Cancer.

Purpose: Distress in cancer is defined as multifactorial unpleasant experience of an emotional, psychological, social, or spiritual nature that interferes with ones' ability to cope with cancer and its symptoms and treatment. The aim of this study was to determine clinical and demographic factors associated with the presence of distress in adolescent and young adults (AYAs) with cancer. Methods: Data were collected as part of a field-test study conducted between August 2016 and November 2017 in Canada (Toronto, Edmonton, and Vancouver) to determine the reliability and validity of CDS-AYA (Cancer Distress Scales for Adolescent and Young Adults). The CDS-AYA consist of five independently functioning scales including impact of cancer, physical, emotional, cognitive, and cancer worry. Multivariate logistic regression analyses, using established CDS-AYA cut points, were performed to identify clinical and demographic factors associated with the presence of distress in AYAs of ages 15-39 years with cancer. Results: Across all scales, increased distress was associated with female gender (p < 0.05), on-treatment status (p < 0.05), and reported poor overall health (p < 0.001). For the emotional scale, distress was also associated with being of age 15-19 years (p = 0.01). The greatest effect size for all scales was associated with treatment status [exp(ß) = 1.78-4.6], except for the cognitive scale where gender had a slightly greater effect size. Conclusion: Factors associated with distress in AYA patients with cancer were similar across five CDS-AYA scales. Although it is important to screen all patients for distress, our findings reveal that patients who are female, on treatment, or who report having poorer health may be at a greater risk.

Multimodal therapy for rigid, persistent avoidant/restrictive food intake disorder (ARFID) since infancy: A case report.

Avoidant/restrictive food intake disorder (ARFID) is a feeding and eating disorder that results in nutritional inadequacies, weight loss, and/or dependence on enteral feeds, and for which three clinical subtypes have been described. We present a unique case of an 11-year-old boy with rigid ARFID since infancy and features of all three ARFID subtypes. The patient presented with a life-long history of sensory aversion, limited intake and phobia of vomiting resulting in restriction to a single food item (yogurt) for more than 5 years. He presented with severe iron-deficiency anaemia, and deficiencies of vitamins A, C, D, E and zinc. We employed a multimodal therapeutic approach that incorporated elements of cognitive-behavioural therapy (CBT), family-based therapy (FBT) and pharmacological management with an antidepressant medication (sertraline) and an atypical antipsychotic agent (olanzapine). Over the course of a 7-week admission, our approach assisted the patient in successful weight restoration and incorporation of at least three new food items into his daily diet. While there are currently no first-line recommendations for ARFID management, our study lends support to the efficacy of CBT, FBT and pharmacological management for ARFID patients, including complex cases with multiple subtype features. Further research is needed to strengthen ARFID clinical guidelines.

A Newborn With Skin Lesions, Thrombocytopenia, and Gastrointestinal Bleeding.

A term infant girl was admitted for evaluation of severe thrombocytopenia. She also had purpura-like skin lesions. A complete blood count showed a platelet count of 40×10/L (normal value: 150 to 400×10/L). She received random donor platelet transfusions and intravenous immunoglobulin therapy; however, thrombocytopenia persisted. She developed bloody stools on day 5 of life and hematemesis on day 9. Upper gastrointestinal endoscopy revealed multiple small, 2 to 5 mm, vascular lesions throughout the stomach body and proximal duodenum. Our multidisciplinary team will discuss an approach towards a term infant with thrombocytopenia and gastrointestinal bleeding, the diagnostic challenges, and patient management.

Fatigue in children and adolescents with immune thrombocytopenia.

Immune thrombocytopenia (ITP), an acquired autoimmune disorder of low platelets and risk of bleeding, has a substantial impact on health-related quality of life (HRQoL). Patients with ITP often report significant fatigue, although the pathophysiology of this is poorly understood. In this observational cohort of 120 children receiving second-line therapies for ITP, we assessed reports of fatigue using the Hockenberry Fatigue Scale. Children and adolescents with ITP reported a similarly high level of fatigue with 54% (29/54) of children and 62% (26/42) of adolescents reporting moderate-to-severe fatigue. There was no correlation between fatigue and age or gender. Adolescents with newly diagnosed and persistent ITP had higher mean fatigue scores than those with chronic ITP (P = 0·03). Fatigue significantly improved in children and adolescents by 1 month after starting second-line treatments, and this improvement continued to be present at 12 months after starting treatment. Fatigue scores at all time-points correlated with general HRQoL using the Kids ITP Tool, but did not correlate with bleeding symptoms, platelet count, or platelet response to treatment. Fatigue is common in children and adolescents with ITP and may benefit from ITP-directed treatment even in the absence of bleeding symptoms.

Androgen therapy in inherited bone marrow failure syndromes: analysis from the Canadian Inherited Marrow Failure Registry.

Progressive cytopenia is a serious complication among paediatric patients with inherited bone marrow failure syndromes (IBMFS). Androgens have been used to improve blood counts in different bone marrow failure conditions. Little is known about efficacy and toxicity with new androgens (i.e., danazol) in different types of IBMFS. We identified 29 patients from the Canadian Inherited Marrow Failure Registry, who received oxymetholone or danazol. Sixteen (55%) had haematological response including patients with unclassified IBMFS (45%). Danazol showed a better toxicity profile and similar efficacy compared to oxymetholone. Androgens are an effective and safe option to ameliorate bone marrow failure in IBMFS.

Cellular and molecular architecture of hematopoietic stem cells and progenitors in genetic models of bone marrow failure.

Inherited bone marrow failure syndromes, such as Fanconi anemia (FA) and Shwachman-Diamond syndrome (SDS), feature progressive cytopenia and a risk of acute myeloid leukemia (AML). Using deep phenotypic analysis of early progenitors in FA/SDS bone marrow samples, we revealed selective survival of progenitors that phenotypically resembled granulocyte-monocyte progenitors (GMP). Whole-exome and targeted sequencing of GMP-like cells in leukemia-free patients revealed a higher mutation load than in healthy controls and molecular changes that are characteristic of AML: increased G>A/C>T variants, decreased A>G/T>C variants, increased trinucleotide mutations at Xp(C>T)pT, and decreased mutation rates at Xp(C>T)pG sites compared with other Xp(C>T)pX sites and enrichment for Cancer Signature 1 (X indicates any nucleotide). Potential preleukemic targets in the GMP-like cells from patients with FA/SDS included SYNE1, DST, HUWE1, LRP2, NOTCH2, and TP53. Serial analysis of GMPs from an SDS patient who progressed to leukemia revealed a gradual increase in mutational burden, enrichment of G>A/C>T signature, and emergence of new clones. Interestingly, the molecular signature of marrow cells from 2 FA/SDS patients with leukemia was similar to that of FA/SDS patients without transformation. The predicted founding clones in SDS-derived AML harbored mutations in several genes, including TP53, while in FA-derived AML the mutated genes included ARID1B and SFPQ. We describe an architectural change in the hematopoietic hierarchy of FA/SDS with remarkable preservation of GMP-like populations harboring unique mutation signatures. GMP-like cells might represent a cellular reservoir for clonal evolution.

Reanalysing genomic data by normalized coverage values uncovers CNVs in bone marrow failure gene panels.

Inherited bone marrow failure syndromes (IBMFSs) are genetically heterogeneous disorders with cytopenia. Many IBMFSs also feature physical malformations and an increased risk of cancer. Point mutations can be identified in about half of patients. Copy number variation (CNVs) have been reported; however, the frequency and spectrum of CNVs are unknown. Unfortunately, current genome-wide methods have major limitations since they may miss small CNVs or may have low sensitivity due to low read depths. Herein, we aimed to determine whether reanalysis of NGS panel data by normalized coverage value could identify CNVs and characterize them. To address this aim, DNA from IBMFS patients was analyzed by a NGS panel assay of known IBMFS genes. After analysis for point mutations, heterozygous and homozygous CNVs were searched by normalized read coverage ratios and specific thresholds. Of the 258 tested patients, 91 were found to have pathogenic point variants. NGS sample data from 165 patients without pathogenic point mutations were re-analyzed for CNVs; 10 patients were found to have deletions. Diamond Blackfan anemia genes most commonly exhibited heterozygous deletions, and included RPS19, RPL11, and RPL5. A diagnosis of GATA2-related disorder was made in a patient with myelodysplastic syndrome who was found to have a heterozygous GATA2 deletion. Importantly, homozygous FANCA deletion were detected in a patient who could not be previously assigned a specific syndromic diagnosis. Lastly, we identified compound heterozygousity for deletions and pathogenic point variants in RBM8A and PARN genes. All deletions were validated by orthogonal methods. We conclude that careful analysis of normalized coverage values can detect CNVs in NGS panels and should be considered as a standard practice prior to do further investigations.

Second-line treatments in children with immune thrombocytopenia: Effect on platelet count and patient-centered outcomes.

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder with isolated thrombocytopenia and hemorrhagic risk. While many children with ITP can be safely observed, treatments are often needed for various reasons, including to decrease bleeding, or to improve health related quality of life (HRQoL). There are a number of available second-line treatments, including rituximab, thrombopoietin-receptor agonists, oral immunosuppressive agents, and splenectomy, but data comparing treatment outcomes are lacking. ICON1 is a prospective, multi-center, observational study of 120 children starting second-line treatments for ITP designed to compare treatment outcomes including platelet count, bleeding, and HRQoL utilizing the Kids ITP Tool (KIT). While all treatments resulted in increased platelet counts, romiplostim had the most pronounced effect at 6 months (P = .04). Only patients on romiplostim and rituximab had a significant reduction in both skin-related (84% to 48%, P = .01 and 81% to 43%, P = .004) and non-skin-related bleeding symptoms (58% to 14%, P = .0001 and 54% to 17%, P = .0006) after 1 month of treatment. HRQoL significantly improved on all treatments. However, only patients treated with eltrombopag had a median improvement in KIT scores at 1 month that met the minimal important difference (MID). Bleeding, platelet count, and HRQoL improved in each treatment group, but the extent and timing of the effect varied among treatments. These results are hypothesis generating and help to improve our understanding of the effect of each treatment on specific patient outcomes. Combined with future randomized trials, these findings will help clinicians select the optimal second-line treatment for an individual child with ITP.

Outcomes indicators and processes in transitional care in adolescents with haemophilia: A Delphi survey of Canadian haemophilia care providers.

INTRODUCTION: It is unclear which outcome indicators should be used to measure the success of haemophilia transition programs, and what are key elements of a haemophilia transition program to ensure success. AIM: To establish by expert consensus a list of important and feasible outcome indicators of successful haemophilia transition, and a list of key elements of transition planning. METHODS: A modified two-stage Delphi survey was developed and disseminated among a panel of Canadian interdisciplinary haemophilia care providers. Participants were asked to rate the importance and feasibility of outcome indicators of effective haemophilia transition and elements of haemophilia transition program. In the second round, participants were asked to choose the top five outcomes suitable for inclusion in a core outcome set of transition effectiveness, and the top five elements that are important and feasible for implementation within the next 5 years. RESULTS: In total, 34/73 (47%) of participants completed the first round and 33 completed the second round, representing a variety of disciplines. Top outcome indicators recommended for a core outcome set include measurement of adherence, change in bleeding rate, self-efficacy skills, haemophilia knowledge, patient and caregiver satisfaction, time gap between last paediatric and first adult clinic, and number of emergency room or hospital admissions. Fourteen elements of transition achieved consensus in importance ratings, while eight were felt to be feasible for implementation within next 5 years. CONCLUSIONS: Results will contribute towards the development of a haemophilia transition outcome instrument and provide guidance for future studies of the effectiveness of transition programs.