Performance Characteristics of Sepsis Screening Tools During Antepartum and Postpartum Admissions

OBJECTIVE

To evaluate the performance characteristics of existing screening tools for the prediction of sepsis during antepartum and postpartum readmissions.

METHODS

This was a case-control study using electronic health record data obtained between 2016 and 2021 from 67 hospitals for antepartum sepsis admissions and 71 hospitals for postpartum readmissions up to 42 days. Patients in the sepsis case group were matched in a 1:4 ratio to a comparison cohort of patients without sepsis admitted antepartum or postpartum. The following screening criteria were evaluated: the CMQCC (California Maternal Quality Care Collaborative) initial sepsis screen, the non-pregnancy-adjusted SIRS (Systemic Inflammatory Response Syndrome), the MEWC (Maternal Early Warning Criteria), UKOSS (United Kingdom Obstetric Surveillance System) obstetric SIRS, and the MEWT (Maternal Early Warning Trigger Tool). Time periods were divided into early pregnancy (less than 20 weeks of gestation), more than 20 weeks of gestation, early postpartum (less than 3 days postpartum), and late postpartum through 42 days. False-positive screening rates, C-statistics, sensitivity, and specificity were reported for each overall screening tool and each individual criterion.

RESULTS

We identified 525 patients with sepsis during an antepartum hospitalization and 728 patients with sepsis during a postpartum readmission. For early pregnancy and more than 3 days postpartum, non-pregnancy-adjusted SIRS had the highest C-statistics (0.78 and 0.83, respectively). For more than 20 weeks of gestation and less than 3 days postpartum, the pregnancy-adjusted sepsis screening tools (CMQCC and UKOSS) had the highest C-statistics (0.87-0.94). The MEWC maintained the highest sensitivity rates during all time periods (81.9-94.4%) but also had the highest false-positive rates (30.4-63.9%). The pregnancy-adjusted sepsis screening tools (CMQCC, UKOSS) had the lowest false-positive rates in all time periods (3.9-10.1%). All tools had the lowest C-statistics in the periods of less than 20 weeks of gestation and more than 3 days postpartum.

CONCLUSION

For admissions early in pregnancy and more than 3 days postpartum, non-pregnancy-adjusted sepsis screening tools performed better than pregnancy-adjusted tools. From 20 weeks of gestation through up to 3 days postpartum, using a pregnancy-adjusted sepsis screening tool increased sensitivity and minimized false-positive rates. The overall false-positive rate remained high.

Racial and Ethnic Disparities in Anemia and Severe Maternal Morbidity

OBJECTIVE

To evaluate antepartum anemia prevalence by race and ethnicity, to assess whether such differences contribute to severe maternal morbidity (SMM), and to estimate the contribution of antepartum anemia to SMM and nontransfusion SMM by race and ethnicity.

METHODS

We conducted a population-based cohort study using linked vital record and birth hospitalization data for singleton births at or after 20 weeks of gestation in California from 2011 through 2020. Pregnant patients with hereditary anemias, out-of-hospital births, unlinked records, and missing variables of interest were excluded. Antepartum anemia prevalence and trends were estimated by race and ethnicity. Centers for Disease Control and Prevention criteria were used for SMM and nontransfusion SMM indicators. Multivariable logistic regression modeling was used to estimate risk ratios (RRs) for SMM and nontransfusion SMM by race and ethnicity after sequential adjustment for social determinants, parity, obstetric comorbidities, delivery, and antepartum anemia. Population attributable risk percentages were calculated to assess the contribution of antepartum anemia to SMM and nontransfusion SMM by race and ethnicity.

RESULTS

In total, 3,863,594 births in California were included. In 2020, Black pregnant patients had the highest incidence of antepartum anemia (21.5%), followed by Pacific Islander (18.2%), American Indian-Alaska Native (14.1%), multiracial (14.0%), Hispanic (12.6%), Asian (10.6%), and White pregnant patients (9.6%). From 2011 to 2020, the prevalence of anemia increased more than100% among Black patients, and there was a persistent gap in prevalence among Black compared with White patients. Compared with White patients, the adjusted risk for SMM was high among most racial and ethnic groups; adjustment for anemia after sequential modeling for known confounders decreased SMM risk most for Black pregnant patients (approximated RR 1.47, 95% CI 1.42-1.53 to approximated RR 1.27, 95% CI 1.22-1.37). Compared with White patients, the full adjusted nontransfusion SMM risk remained high for most groups except Hispanic and multiracial patients. Within each racial and ethnic group, the population attributable risk percentage for antepartum anemia and SMM was highest for multiracial patients (21.4%, 95% CI 17.5-25.0%), followed by Black (20.9%, 95% CI 18.1-23.4%) and Hispanic (20.9%, 95% CI 19.9-22.1%) patients. The nontransfusion SMM population attributable risk percentages for Asian, Black, and White pregnant patients were less than 8%.

CONCLUSION

Antepartum anemia, most prevalent among Black pregnant patients, contributed to disparities in SMM by race and ethnicity. Nearly one in five to six SMM cases among Black, Hispanic, American Indian-Alaska Native, Pacific Islander, and multiracial pregnant patients is attributable in part to antepartum anemia.

Alliance for Innovation on Maternal Health: Consensus Bundle on Sepsis in Obstetric Care

Sepsis in obstetric care is one of the leading causes of maternal death in the United States, with Black, Asian/Pacific Islander, and American Indian/Alaska Native obstetric patients experiencing sepsis at disproportionately higher rates. State maternal mortality review committees have determined that deaths are preventable much of the time and are caused by delays in recognition, treatment, and escalation of care. The "Sepsis in Obstetric Care" patient safety bundle provides guidance for health care teams to develop coordinated, multidisciplinary care for pregnant and postpartum people by preventing infection and recognizing and treating infection early to prevent progression to sepsis. This is one of several core patient safety bundles developed by AIM (the Alliance for Innovation on Maternal Health) to provide condition- or event-specific clinical practices that should be implemented in all appropriate care settings. As with other bundles developed by AIM, the "Sepsis in Obstetric Care" patient safety bundle is organized into five domains: Readiness, Recognition and Prevention, Response, Reporting and Systems Learning, and Respectful, Equitable, and Supportive Care. The Respectful, Equitable, and Supportive Care domain provides essential best practices to support respectful, equitable, and supportive care to all patients. Further health equity considerations are integrated into the elements of each domain.

Risk factors and pregnancy outcomes vary among Asian American, Native Hawaiian, and Pacific Islander individuals giving birth in California

OBJECTIVE

To compare frequencies of risk factors and pregnancy outcomes in ethnic groups versus the combined total of Asian American, Native Hawaiian, and Pacific Islander (AANHPI) populations.

METHODS

Using linked birth and fetal death certificate and maternal hospital discharge data (California 2007-2018), we estimated frequencies of 15 clinical and sociodemographic exposures and 11 pregnancy outcomes. Variability across 15 AANHPI groups was compared using a heat map and compared to frequencies for the total group (n = 904,232).

RESULTS

AANHPI groups varied significantly from each other and the combined total regarding indicators of social disadvantage (e.g., range for high school-level educational or less: 6.4% Korean-55.8% Samoan) and sociodemographic factors (e.g., maternal age <20 years: 0.2% Chinese-8.8% Guamanian) that are related to adverse pregnancy outcomes. Perinatal outcomes varied significantly (e.g., severe maternal morbidity: 1.2% Korean-1.9% Filipino). No single group consistently had risk factors or outcome prevalence at the extremes, i.e., no group was consistently better or worse off across examined factors.

CONCLUSIONS

Substantial variability in perinatal risk factors and outcomes exists across AANHPI groups. Aggregation into "AANHPI" is not appropriate for outcome reporting.

Racial/ethnic disparities in severe maternal morbidity: An intersectional lifecourse approach

Despite long-existing calls to address alarming racial/ethnic gaps in severe maternal morbidity (SMM), research that considers the impact of intersecting social inequities on SMM risk remains scarce. Invoking intersectionality theory, we sought to assess SMM risk at the nexus of racial/ethnic marginalization, weathering, and neighborhood/individual socioeconomic disadvantage. We used birth hospitalization records from California across 20 years (1997-2017, N = 9,806,406) on all live births ≥20 weeks gestation. We estimated adjusted average predicted probabilities of SMM at the combination of levels of race/ethnicity, age, and neighborhood deprivation or individual socioeconomic status (SES). The highest risk of SMM was observed among Black birthing people aged ≥35 years who either resided in the most deprived neighborhoods or had the lowest SES. Black birthing people conceptualized to be better off due to their social standing (aged 20-34 years and living in the least deprived neighborhoods or college graduates) had comparable and at times worse risk than White birthing people conceptualized to be worse off (aged ≥35 years and living in the most deprived neighborhoods or had a high-school degree or less). Our findings highlight the need to explicitly address structural racism as the driver of racial/ethnic health inequities and the imperative to incorporate intersectional approaches.

Severe Maternal Morbidity: A Comparison of Definitions and Data Sources

Severe maternal morbidity (SMM) is a composite outcome measure that indicates serious, potentially life-threatening maternal health problems. There is great interest in defining SMM using administrative data for surveillance and research. In the United States, one common way of defining SMM at the population level is an index developed by the Centers for Disease Control and Prevention. Modifications to this index (e.g., exclusion of maternal blood transfusion) have been proposed; some research defines SMM using an index introduced by Bateman et al. (Obstet Gynecol. 2013;122(5):957-965). Birth certificate data are also increasingly being used to define SMM. We compared commonly used US definitions of SMM among all California births (2007-2012) using the kappa (κ) statistic and other measures. We also evaluated agreement between maternal morbidity fields on the birth certificate as compared with health insurance claims data. Concordance between the 7 definitions of SMM analyzed was generally low (i.e., κ < 0.41 for 13 of 21 two-way comparisons). Low concordance was particularly driven by the presence/absence of transfusion and claims data versus birth certificate definitions. Low agreement between administrative data-based definitions of SMM highlights that results can be expected to differ between them. Further research on validity of SMM definitions, using more fine-grained data sources, is needed.

Birth hospital and racial and ethnic differences in severe maternal morbidity in the state of California

BACKGROUND

Birth hospital has recently emerged as a potential key contributor to disparities in severe maternal morbidity, but investigations on its contribution to racial and ethnic differences remain limited.

OBJECTIVE

We leveraged statewide data from California to examine whether birth hospital explained racial and ethnic differences in severe maternal morbidity.

STUDY DESIGN

This cohort study used data on all births at ≥20 weeks gestation in California (2007-2012). Severe maternal morbidity during birth hospitalization was measured using the Centers for Disease Control and Prevention index of having at least 1 of the 21 diagnoses and procedures (eg, eclampsia, blood transfusion, hysterectomy). Mixed-effects logistic regression models (ie, women nested within hospitals) were used to compare racial and ethnic differences in severe maternal morbidity before and after adjustment for maternal sociodemographic and pregnancy-related factors, comorbidities, and hospital characteristics. We also estimated the risk-standardized severe maternal morbidity rates for each hospital (N=245) and the percentage reduction in severe maternal morbidity if each group of racially and ethnically minoritized women gave birth at the same distribution of hospitals as non-Hispanic white women.

RESULTS

Of the 3,020,525 women who gave birth, 39,192 (1.3%) had severe maternal morbidity (2.1% Black; 1.3% US-born Hispanic; 1.3% foreign-born Hispanic; 1.3% Asian and Pacific Islander; 1.1% white; 1.6% American Indian and Alaska Native, and Mixed-race referred to as Other). Risk-standardized rates of severe maternal morbidity ranged from 0.3 to 4.0 per 100 births across hospitals. After adjusting for covariates, the odds of severe maternal morbidity were greater among nonwhite women than white women in a given hospital (Black: odds ratio, 1.25; 95% confidence interval, 1.19-1.31); US-born Hispanic: odds ratio, 1.25; 95% confidence interval, 1.20-1.29; foreign-born Hispanic: odds ratio, 1.17; 95% confidence interval, 1.11-1.24; Asian and Pacific Islander: odds ratio, 1.26; 95% confidence interval, 1.21-1.32; Other: odds ratio, 1.31; 95% confidence interval, 1.15-1.50). Among the studied hospital factors, only teaching status was associated with severe maternal morbidity in fully adjusted models. Although 33% of white women delivered in hospitals with the highest tertile of severe maternal morbidity rates compared with 53% of Black women, birth hospital only accounted for 7.8% of the differences in severe maternal morbidity comparing Black and white women and accounted for 16.1% to 24.2% of the differences for all other racial and ethnic groups.

CONCLUSION

In California, excess odds of severe maternal morbidity among racially and ethnically minoritized women were not fully explained by birth hospital. Structural causes of racial and ethnic disparities in severe maternal morbidity may vary by region, which warrants further examination to inform effective policies.

Racial and Ethnic Disparities in Hospital-Based Care Associated with Postpartum Depression

OBJECTIVE

To estimate racial and ethnic differences in rates of hospital-based care associated with postpartum depression.

METHODS

This is a retrospective cohort study using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes within data from the Office of Statewide Planning and Development in California. We included primiparous women who underwent delivery hospitalization from 2008 to 2012. The primary outcome was the first postpartum hospital encounter with a ICD-9-CM code for depression over a 9-month period after delivery. We examined the cumulative incidence of hospital-based care for postpartum depression by race/ethnicity. Logistic regression was used to estimate relative risk.

RESULTS

The study cohort consisted of 984,167 primiparous women: 314,037 (32%) were non-Hispanic White; 59,754 (6%) were non-Hispanic Black; 150,855 (15%) were non-Hispanic Asian; 448,770 (46%) were Hispanic; and 10,399 (1%) were other races. The cumulative incidence of hospital-based care for postpartum depression was highest for Black women (39; 95% CI = 34-44 per 10,000 deliveries) and lowest for Asian women (7; 95% CI = 5-8 per 10,000 deliveries). Compared with White women, hospital-based care for postpartum depression was more likely to be provided to Black women (OR = 2.3; 95% CI = 1.9-2.7), whereas care was less likely for Asians (OR = 0.4; 95% CI = 0.3-0.5) and Hispanics (OR = 0.8; 95% CI = 0.7-1.0). Similar findings were observed after excluding women with antepartum depression, adjusting for sociodemographic and clinical variables, and stratifying according to care settings.

CONCLUSION

Compared with White women, hospital-based care for postpartum depression more frequently impacts Black women. Identifying and improving inequities in access to and utilization of mental health care for postpartum women should be a maternal health priority.

Measuring labor and delivery unit culture and clinicians' attitudes toward birth: Revision and validation of the Labor Culture Survey

BACKGROUND

Cesarean delivery rates in the United States vary widely between hospitals, which cannot be fully explained by hospital or patient factors. Cultural factors are hypothesized to play a role in cesarean overuse, yet tools to measure labor culture are lacking. The aim of this study was to revise and validate a survey tool to measure hospital culture specific to cesarean overuse.

METHODS

A panel of clinicians and researchers compiled an item bank from validated surveys, added newly created items, and performed four rounds of iterative revision and consolidation. Obstetricians, family physicians, midwives, anesthesiologists, and labor nurses were recruited from 79 hospitals in California. Exploratory factor analysis was used to reduce the number of survey items and identify latent constructs to form the basis of subscales. Confirmatory factor analysis examined reliability in 31 additional hospitals. Poisson regression assessed associations between hospitals' mean score on each individual item and cesarean rates.

RESULTS

A total of 1718 individuals from 70 hospitals were included in the exploratory factor analysis. The final Labor Culture Survey (LCS) consisted of 29 items and six subscales: "Best Practices to Reduce Cesarean Overuse," "Fear of Vaginal Birth," "Unit Microculture," "Physician Oversight," "Maternal Agency," and "Cesarean Safety."

CONCLUSIONS

The revised LCS is a valid and reliable tool to measure constructs shown to be associated with cesarean rates. These findings support prior research that has shown that hospital culture is measurable, and that clinician attitudes are predictive of clinician behaviors. Unique to our survey is the construct of labor and delivery unit microculture.

Cesarean overuse and the culture of care

OBJECTIVE

To assess hospital unit culture and clinician attitudes associated with varying rates of primary cesarean delivery.

DATA SOURCES/STUDY SETTING

Intrapartum nurses, midwives, and physicians recruited from 79 hospitals in California participating in efforts to reduce cesarean overuse.

STUDY DESIGN

Labor unit culture and clinician attitudes measured using a survey were linked to the California Maternal Data Center for birth outcomes and hospital covariates.

METHODS

Association with primary cesarean delivery rates was assessed using multivariate Poisson regression adjusted for hospital covariates.

PRINCIPAL FINDINGS

1718 respondents from 70 hospitals responded to the Labor Culture Survey. The "Unit Microculture" subscale was strongly associated with primary cesarean rate; the higher a unit scored on 8-items describing a culture supportive of vaginal birth (eg, nurses are encouraged to spend time in rooms with patients, and doulas are welcomed), the cesarean rate decreased by 41 percent (95% CI = -47 to -35 percent, P < 0.001). Discordant attitudes between nurses and physicians were associated with increased cesarean rates.

CONCLUSIONS

Hospital unit culture, clinician attitudes, and consistency between professions are strongly associated with primary cesarean rates. Improvement efforts to reduce cesarean overuse must address culture of care as a key part of the change process.

Standardized outcome measures for pregnancy and childbirth, an ICHOM proposal

BACKGROUND

Value-based health care aims to optimize the balance of patient outcomes and health care costs. To improve value in perinatal care using this strategy, standard outcomes must first be defined. The objective of this work was to define a minimum, internationally appropriate set of outcome measures for evaluating and improving perinatal care with a focus on outcomes that matter to women and their families.

METHODS

An interdisciplinary and international Working Group was assembled. Existing literature and current measurement initiatives were reviewed. Serial guided discussions and validation surveys provided consumer input. A series of nine teleconferences, incorporating a modified Delphi process, were held to reach consensus on the proposed Standard Set.

RESULTS

The Working Group selected 24 outcome measures to evaluate care during pregnancy and up to 6 months postpartum. These include clinical outcomes such as maternal and neonatal mortality and morbidity, stillbirth, preterm birth, birth injury and patient-reported outcome measures (PROMs) that assess health-related quality of life (HRQoL), mental health, mother-infant bonding, confidence and success with breastfeeding, incontinence, and satisfaction with care and birth experience. To support analysis of these outcome measures, pertinent baseline characteristics and risk factor metrics were also defined.

CONCLUSIONS

We propose a set of outcome measures for evaluating the care that women and infants receive during pregnancy and the postpartum period. While validation and refinement via pilot implementation projects are needed, we view this as an important initial step towards value-based improvements in care.

Effect of inspiratory rise time on sputum movement during ventilator hyperinflation in a test lung model

OBJECTIVES

Physiotherapists may use ventilator hyperinflation to enhance secretion clearance for intubated patients. This study investigated the effects of altering percentage inspiratory rise time (IRT) on sputum movement, ratio of peak inspiratory to expiratory flow rate (PIF:PEF ratio) and net peak expiratory flow (PEF) during ventilator hyperinflation in a test lung model.

DESIGN

Laboratory-based bench study.

INTERVENTIONS

Simulated sputum (two viscosities) was inserted into clean, clear tubing and connected between a ventilator and a resuscitation bag. Thirty-six ventilator hyperinflation breaths were applied for each 5% incremental increase in IRT between 0% and 20%.

MAIN OUTCOME MEASURES

The primary outcome was sputum displacement (cm). Secondary outcomes included PIF:PEF ratio and net PEF.

RESULTS

Significant cephalad sputum movement of 2.42cm (1.59 to 3.94) occurred with IRT between 5% and 20%, compared with caudad movement of 0.53 cm (0.31 to 1.53) at 0% IRT (median sputum movement difference 3.7cm, 95% confidence interval 2.2 to 4.8, P<0.001). Incremental increases in IRT percentage produced linear enhancements in PIF:PEF ratio and net PEF for both sputum concentrations (P<0.001). However, once the critical threshold for PIF:PEF ratio of 0.9 was achieved, the distance of sputum movement remained consistent for all IRT values exceeding 5%.

CONCLUSIONS

Significant increases in sputum movement occurred when IRT percentage was lengthened to achieve the optimal PIF:PEF ratio, irrespective of sputum viscosity. This provides a theoretical rationale for therapists to consider this technique when treating mechanically ventilated patients. As no additional sputum movement was seen beyond the critical PIF:PEF ratio threshold, a low IRT percentage may potentially be used to achieve effective sputum movement.

The National Network of State Perinatal Quality Collaboratives: A Growing Movement to Improve Maternal and Infant Health

State Perinatal Quality Collaboratives (PQCs) are networks of multidisciplinary teams working to improve maternal and infant health outcomes. To address the shared needs across state PQCs and enable collaboration, Centers for Disease Control and Prevention (CDC), in partnership with March of Dimes and perinatal quality improvement experts from across the country, supported the development and launch of the National Network of Perinatal Quality Collaboratives (NNPQC). This process included assessing the status of PQCs in this country and identifying the needs and resources that would be most useful to support PQC development. National representatives from 48 states gathered for the first meeting of the NNPQC to share best practices for making measurable improvements in maternal and infant health. The number of state PQCs has grown considerably over the past decade, with an active PQC or a PQC in development in almost every state. However, PQCs have some common challenges that need to be addressed. After its successful launch, the NNPQC is positioned to ensure that every state PQC has access to key tools and resources that build capacity to actively improve maternal and infant health outcomes and healthcare quality.

Opportunities for maternal transport for delivery of very low birth weight infants

OBJECTIVE

To assess frequency of very low birth weight (VLBW) births at non-level III hospitals.

STUDY DESIGN

Retrospective cohort study using linked California birth certificate and discharge data of 2008 to 2010 for deliveries of singleton or first-born infant of multiple gestations with birth weight 400 to 1500 g. Delivery rates by neonatal level of care were obtained. Risk of delivery at non-level III centers was estimated in univariable and multivariable models.

RESULTS

Of the 1 508 143 births, 13 919 (9.2%) were VLBW; birth rate at non-level III centers was 14.9% (8.4% in level I and 6.5% in level II). Median rate of VLBW births was 0.3% (range 0 to 4.7%) annually at level I and 0.5% (range 0 to 1.6%) at level II hospitals. Antepartum stay for >24 h occurred in 14.0% and 26.9% of VLBW births in level I and level II hospitals, respectively.

CONCLUSION

Further improvement is possible in reducing VLBW infant delivery at suboptimal sites, given the window of opportunity for many patients.

The Impact of maternal obesity and race/ethnicity on perinatal outcomes: Independent and joint effects

OBJECTIVE

Independent and joint impacts of maternal race/ethnicity and obesity on adverse birth outcomes, including pre-eclampsia, low birth weight, and macrosomia, were characterized.

METHODS

Retrospective cohort study of all 2007 California births was conducted using vital records and claims data. Maternal race/ethnicity and maternal body mass index (BMI) were the key exposures; their independent and joint impact on outcomes using regression models was analyzed.

RESULTS

Racial/ethnic minority women of normal weight generally had higher risk as compared with white women of normal weight (e.g., African-American women, pre-eclampsia adjusted odds ratio [aOR] 1.60, 95% confidence interval [CI]: 1.48-1.74 vs. white women). However, elevated BMI did not usually confer additional risk (e.g., pre-eclampsia aOR comparing African-American women with excess weight with white women with excess weight, 1.17, 95% CI: 0.89-1.54). Obesity was a risk factor for low birth weight only among white women (excess weight aOR, 1.24, 95% CI: 1.04-1.49 vs. white women of normal weight) and not among racial/ethnic minority women (e.g., African-American women, 0.95, 95% CI: 0.83-1.08).

CONCLUSIONS

These findings add nuance to our understanding of the interplay between maternal race/ethnicity, BMI, and perinatal outcomes. While the BMI/adverse outcome gradient appears weaker in racial/ethnic minority women, this reflects the overall risk increase in racial/ethnic minority women of all body sizes.

Factors affecting the Haemophilia Joint Health Score in children with severe haemophilia

Joint damage from bleeding episodes leads to physical or functional limitations in people with haemophilia. Various factors may influence the frequency and severity of joint damage. This study examined whether age, prophylaxis, history of high-titre inhibitors (HTI) and bleeding events influenced the Haemophilia Joint Health Score (HJHS) in children. Medical and physiotherapy notes of boys with severe haemophilia, aged 4-18 years, were reviewed to identify factors associated with increased HJHS. The HJHS of 83 boys (median age: 11) ranged from 0 to 25, with 44/83 (53%) having a score of zero. The median HJHS was 0 (mean 2.6). In the non-HTI group, the HJHS for boys on late prophylaxis was 2.68 times higher than those who started early and the HJHS was on average 10% higher for every additional recent bleed. In this group the odds of having a zero score fell by 30% for every year increase in age. Boys with a history of HTI had higher HJHS scores than the non-HTI group, and age, number of recent bleeds and tolerized status were positively associated with HJHS. The score rose on average by 28% for every year of age and by 76% for non-tolerized boys. This study provides further evidence supporting early prophylaxis use and the importance of immune tolerance therapy. The HJHS is a useful tool for identifying and tracking changes in joint health with respect to therapy or disease progression. With improvements in haemophilia treatment, the disproportionate number of zero scores will continue to make interpretation of the HJHS challenging.