Patients' experiences of lupus-related foot problems: a qualitative investigation.

Background Systemic lupus erythematosus (SLE) can present with a variety of symptoms. Previous research has shown there is a high prevalence of lower limb and foot problems in patients with SLE associated with the musculoskeletal, vascular and neurological changes. Furthermore, there is a high prevalence of infections affecting the feet and a range of common skin and nail problems. However, it is not known how these foot problems impact upon people's lives. Therefore, we aimed to explore this using a qualitative approach. Method Following ethical approval, 12 participants were recruited who had a diagnosis of SLE, current and/or past experience of foot problems and were over 18 years in age. Following consent, interviews were carried out with an interpretivist phenomenological approach to both data collection and analysis. Results Seven themes provide insight into: foot problems and symptoms; the impact of these foot problems and symptoms on activities; disclosure and diagnosis of foot problems; treatment of foot problems and symptoms; perceived barriers to professional footcare; unanswered questions about feet and footcare; and identification of the need for professional footcare and footcare advice. Conclusion These participants tend to "self-treat" rather than disclose that they may need professional footcare. A lack of focus upon foot health within a medical consultation is attributed to the participant's belief that it is not within the doctor's role, even though it is noted to contribute to reduced daily activity. There is a need for feet to be included as a part of patient monitoring and for foot health management to be made accessible for people with SLE.

The prevalence of self-reported lower limb and foot health problems experienced by participants with systemic lupus erythematosus: Results of a UK national survey.

Objective The main aim of this survey was to determine the frequency of self-reported lower limb or foot and ankle complications experienced by participants with systemic lupus erythematosus (SLE). A secondary aim was to determine the frequency of treatments that have been received or that participants with SLE may like to receive if offered. Method A quantitative, cross-sectional, self-reported survey design was utilized. The developed survey was checked for face and content validity prior to patient partner cognitive debriefing in order to ensure usability, understanding of the process of completion and of the questions posed. The full protocol for survey development has been published previously. Results This is the first comprehensive national UK survey of lower limb and foot health problems reported by participants with SLE. A high prevalence of vascular, dermatological and musculoskeletal complications was reported by survey respondents. Additionally, whilst the relative prevalence of sensory loss was low, a quarter of people reported having had a fall related to changes in foot sensation demonstrating a previously unknown rate and cause of falls. Conclusion Complications related to vascular, dermatological and musculoskeletal health are identified as particularly prevalent in participants with SLE. Further, there is a suggestion that the provision of interventions to maintain lower limb health is highly varied and lacks national standardization, despite there being a strong indication of participant reported need. The findings of this work can be used to inform care guideline development in addition to identifying areas for future research.

Health literacy and pap testing in insured women.

Several studies have found a link between health literacy and participation in cancer screening. Most, however, have relied on self-report to determine screening status. Further, until now, health literacy measures have assessed print literacy only. The purpose of this study was to examine the relationship between participation in cervical cancer screening (Papanicolaou [Pap] testing) and two forms of health literacy-reading and listening. A demographically diverse sample was recruited from a pool of insured women in Georgia, Massachusetts, Hawaii, and Colorado between June 2009 and April 2010. Health literacy was assessed using the Cancer Message Literacy Test-Listening and the Cancer Message Literacy Test-Reading. Adherence to cervical cancer screening was ascertained through electronic administrative data on Pap test utilization. The relationship between health literacy and adherence to evidence-based recommendations for Pap testing was examined using multivariate logistic regression models. Data from 527 women aged 40 to 65 were analyzed and are reported here. Of these 527 women, 397 (75 %) were up to date with Pap testing. Higher health literacy scores for listening but not reading predicted being up to date. The fact that health literacy listening was associated with screening behavior even in this insured population suggests that it has independent effects beyond those of access to care. Patients who have difficulty understanding spoken recommendations about cancer screening may be at risk for underutilizing screening as a result.

'Focus on feet'--the effects of systemic lupus erythematosus: a narrative review of the literature.

BACKGROUND: The manifestations of systemic lupus erythematosus (SLE) vary between individuals, from the severe and life-threatening renal and central nervous system involvement, to the involvement of skin, musculoskeletal and vascular system, and the complications of infection influencing the quality of life. However, as specific manifestations affecting the lower limb are perceived as receiving little focus, the purpose of this narrative literature review is to identify the specific factors associated with SLE that may have implications for lower limb and foot morbidity. METHOD: A structured search of databases was conducted. The inclusion was restricted to publications in the English language, those that specifically investigate the feet as affected with SLE. No restriction on year of publication was imposed to reduce publication bias and to capture as many publication in relation to feet. RESULTS: Eleven papers fulfilled the inclusion criteria. There were seven additional papers that made observations related to the articular or vascular complications of the feet. This narrative review provides some information on how SLE affects the lower limb and foot in relation to the musculoskeletal and vascular systems. However, there is a lack of literature that specifically focuses on all the manifestations of SLE and the complications associated with its management. DISCUSSION: There are indications that SLE affects lower limb and foot morbidity but the scale of these problems is unclear and this is partly because of the absence of research and the lack of a 'gold standard' framework for the assessment of the lower limb and foot. In addition to clinical foot health assessment, ultrasonography may be a useful alternative to plain film radiography or magnetic resonance imaging (MRI) in capturing the extent of articular and extra-articular manifestations. Further, the Ankle Brachial Pressure Index (ABPI) may be useful in identifying those with atherosclerosis and ischaemia. CONCLUSION: There are indications that SLE affects lower limb and foot morbidity but the scale of these problems and effective management of them is unclear. Therefore, further research is warranted in order to better understand the impact of SLE on the foot and lower limb and its impact on quality of life.

Alternating verbal fluency performance following bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease.

BACKGROUND AND PURPOSE: Despite common occurrences of verbal fluency declines following bilateral subthalamic nucleus deep brain stimulation (STN-DBS) for the treatment of Parkinson's disease (PD), alternating fluency measures using cued and uncued paradigms have not been evaluated. METHODS: Twenty-three STN-DBS patients were compared with 20 non-surgical PD patients on a comprehensive neuropsychological assessment, including cued and uncued intradimensional (phonemic/phonemic and semantic/semantic) and extradimensional (phonemic/semantic) alternating fluency measures at baseline and 6-month follow-up. RESULTS: STN-DBS patients demonstrated a greater decline on the cued phonemic/phonemic fluency and the uncued phonemic/semantic fluency tasks compared to the PD patients. For STN-DBS patients, verbal learning and information processing speed accounted for a significant proportion of the variance in declines in alternating phonemic/phonemic and phonemic/semantic fluency scores, respectively, whilst only naming was related to uncued phonemic/semantic performance for the PD patients. Both groups were aided by cueing for the extradimensional task at baseline and follow-up, and the PD patients were also aided by cueing for the phonemic/phonemic task on follow-up. CONCLUSIONS: These findings suggest that changes in alternating fluency are not related to disease progression alone as STN-DBS patients demonstrated greater declines over time than the PD patients, and this change was related to declines in information processing speed.

The burden of unscheduled health care for asthma in Latin America.

OBJECTIVES: To determine the level and cost of unscheduled health care resource use in adults and children across all asthma symptom severities in Latin America. METHODS: The level and cost of health care resource use were analysed for 2074 patients with asthma included in the Asthma Insights and Reality in Latin America (AIRLA) survey from 10 Latin American countries. Health care resource use was multiplied by country-specific unit costs to estimate average per-patient annual costs. Patients were classified as adults (> or = 16 years) or children (<16 years), with disease severity categorized using a symptom severity index. RESULTS: Persistent asthma symptoms were experienced by 53.1% of patients (50.1% of children and 54.6% of adults). In the year preceding the survey, 57.1% of patients required unscheduled health care resource use and 45.1% reported at least 1 emergency hospital contact. The percentage of patients reporting unscheduled health care resource use was greatest amongst those with severe persistent symptoms (71.9%) but it was also high in those with mild intermittent symptoms (45.7%). An average of 73.2% of annual costs of asthma-related health care for the 10 countries was due to unscheduled health care. Expenditure on unscheduled care was greatest amongst both adults and children with severe persistent asthma symptoms (US $558 and US $769, respectively). Adults and children with mild intermittent symptoms also incurred considerable unscheduled costs (US $204 and US $215, respectively). CONCLUSIONS: Poorly controlled asthma imposes a considerable cost burden driven by unscheduled health care resource use in Latin America. Treatments to control asthma and reduce the need for unscheduled health care could reduce this cost in both adults and children.

First steps: Parent health behaviours related to children's foot health.

Good foot health throughout childhood is important but remains poorly understood with few studies exploring this topic. The aim of this study was to define parents' knowledge, practices and health-related perceptions of children's feet. A qualitative design was adopted. Semi-structured, one-to-one interviews were carried out with parents of children aged five years and under, recruited from South East and North West of England. Interviews explored parents' views, beliefs and understanding of foot health in infancy and early childhood. Transcripts of the interviews were analysed using thematic analysis. Eighteen interviews were conducted. Seven themes were identified relating to (1) parents belief and knowledge about children's foot health; (2) how parents use and share foot health information; (3) activities for supporting foot health and development; (4) footwear choices, beliefs and influences; (5) the way they access health professionals; (6) the way they search for foot health information and (7) developing practice(s) to support parents. The study provides the first insight into how parents view foot health in early infancy and childhood. The findings highlight the key foot health beliefs important to parents, how they learn about and what influences their decision-making about caring for children's feet, the way parents receive and seek information, and how they access support for foot health concerns. The findings highlight the need for accurate, clear and consistent foot health messages, and the important role health professionals have in signposting parents towards reliable and informative sources on foot health.

Seroprevalence and epidemiological correlates of HTLV-I infection in U.S. blood donors.

Screening for human T-lymphotropic virus type I (HTLV-I) antibodies was performed on sera from 39,898 blood donors at eight blood centers in geographically distinct areas of the United States. Ten donors (0.025 percent) showed evidence of HTLV-I seropositivity by enzyme immunoassays; this was confirmed by protein immunoblot and radioimmunoprecipitation. Seroprevalence rates ranged from 0 to 0.10 percent at the locations sampled, with HTLV-I antibodies found predominantly in donors from the southeastern and southwestern United States. Matched case-control interviews and laboratory studies were performed on five seropositive women and two seropositive men who participated in an identity-linked collection of sera from a subset of 33,893 donors at six of the eight blood centers. Four of the women and both men are black; one woman is Caucasian. Four of the seven seropositive individuals admitted to prior intravenous drug abuse or sexual contact with an intravenous drug user. Sexual contact with native inhabitants of an HTLV-I endemic area was the only identified risk factor for one male. The distribution of HTLV-I antibodies in this U.S. blood donor sample corroborates the previously reported epidemiology of this agent and suggests that additional donor screening measures, including the testing of donated blood for HTLV-I markers, may be necessary to prevent the spread of HTLV-I to transfusion recipients.

Work participation, mobility and foot symptoms in people with systemic lupus erythematosus: findings of a UK national survey.

OBJECTIVE: The aim of this study was to investigate whether foot and lower limb related symptoms were associated with work participation and poor mobility in people with Systemic Lupus Erythematosus (SLE). METHOD: A quantitative, cross-sectional, self-reported survey design was utilised. People with SLE from six United Kingdom (UK) treatment centres and a national register were invited to complete a survey about lower limb and foot health, work participation and mobility. Data collected included work status and the prevalence of foot symptoms. The focus of the analyses was to explore potential associations between poor foot health work non-participation. RESULTS: In total, 182 useable surveys were returned. Seventy-nine respondents reported themselves as employed and 32 reported work non-participation. The remaining were retired due to age or reported work non-participation for other reasons. Work non-participation due to foot symptoms was significantly associated with difficulty walking (p = 0.024), past episodes of foot swelling (p = 0.041), and past episodes of foot ulceration (p = 0.018). There was a significant increase in foot disability scores amongst those not working (mean 18.13, 95% CI: 14.85-21.41) compared to those employed (mean 10.16, 95% CI: 8.11-12.21). CONCLUSIONS: Twenty-nine% of people with SLE reported work non-participation because of lower limb or foot problems. Our results suggest that foot health and mobility may be important contributors to a persons' ability to remain in work and should be considered as part of a clinical assessment.

National profile of foot orthotic provision in the United Kingdom, part 2: podiatrist, orthotist and physiotherapy practices.

BACKGROUND: A national survey recently provided the first description of foot orthotic provision in the United Kingdom. This article aims to profile and compare the foot orthoses practice of podiatrists, orthotists and physiotherapists within the current provision. METHOD: Quantitative data were collected from podiatrists, orthotists and physiotherapists via an online questionnaire. The topics, questions and answers were developed through a series of pilot phases. The professions were targeted through electronic and printed materials advertising the survey. Data were captured over a 10 month period in 2016. Differences between professions were investigated using Chi squared and Fischer's exact tests, and regression analysis was used to predict the likelihood of each aspect of practice in each of the three professions. RESULTS: Responses from 357 podiatrists, 93 orthotists and 49 physiotherapists were included in the analysis. The results reveal statistically significant differences in employment and clinical arrangements, the clinical populations treated, and the nature and volume of foot orthoses caseload. CONCLUSION: Podiatrists, orthotists and physiotherapists provide foot orthoses to important clinical populations in both a prevention and treatment capacity. Their working context, scope of practice and mix of clinical caseload differs significantly, although there are areas of overlap. Addressing variations in practice could align this collective workforce to national allied health policy.

National profile of foot orthotic provision in the United Kingdom, part 1: practitioners and scope of practice.

BACKGROUND: Foot orthoses have been advocated in the management of a wide range of clinical foot and lower limb problems and are within the scope of podiatry, orthotic and physiotherapy practice. Previous reports into the provision of orthoses have consistently identified significant issues with services and devices, but data were never specific to foot orthoses. The aim of this first of a series of papers was to report the first ever national multi professional profile of foot orthosis provision in the United Kingdom. METHODS: Quantitative and qualitative data were collected from podiatrists, orthotists and physiotherapists via an online questionnaire. The topics, questions and answers were developed through a series of pilot phases. The professions were targeted through electronic and printed materials. Data were captured over a 10 month period in 2016. RESULTS: A total of 499 responses were included in analysis, including 357 podiatrists, 93 orthotists and 49 physiotherapists. The results reveal wide ranging practices across podiatrists, orthotists and physiotherapists, provision of orthoses through different health care departments (uni and multidisciplinary), for different health conditions (acute and chronic), and involving different types of orthoses (prefabricated and customised). CONCLUSION: Foot orthoses in the United Kingdom are provided in areas of well recognised health and rehabilitation priorities. A wide range of orthotic devices and practices are employed and different professions provide foot orthoses in different ways.

Patient perceptions of stock footwear design features.

Patients with diseases which impact on foot health, for example diabetes and rheumatoid arthritis, are known to have some benefit from prescribed stock footwear with regards to clinical outcomes. Achieving this is not just about getting the footwear designed and fitted to meet the clinical needs, but it also requires that the patient wears the shoes. This means meeting the non-clinical needs or criteria of patients. The aim of this study was to compare perceptions of the same footwear between patients with diabetes and patients with rheumatoid arthritis (RA) with regard to specific design features. Fifty-four patients with RA and 40 patients with diabetes who required prescription footwear were asked to identify issues of importance, and to assess the features of five different pairs of stock footwear using a Likert scale scoring form. There was a difference between the RA and the diabetes groups with regards their overall requirements from the footwear with comfort being a priority in RA and style a priority for diabetes. Both groups rated the same footwear as overall best from the selection, but the scores suggest that there were features with the 'best' shoe which were not acceptable suggesting that even the 'best' shoe was a compromise This possibly indicates that existing footwear ranges do not meet all the patients' requirements. Patients have different perceptions with regard to what is important to them in terms of footwear with regards to the specific features of the footwear and one of the influences appears to be the underlying systemic disease. Patient-based criteria may be an important consideration in the design of the footwear.

Transmission of human T-lymphotropic virus types I and II by blood transfusion. A retrospective study of recipients of blood components (1983 through 1988). The American Red Cross HTLV-I/II Collaborative Study Group.

We studied results of a "lookback" program involving laboratory testing and interviews of 133 recipients of prior donations from blood donors seropositive for human T-lymphotropic virus types I and II (HTLV-I/II) identified at 28 American Red Cross blood centers. The study was designed to explore the natural course of posttransfusion HTLV-I/II infection among individuals who received blood components from donors subsequently identified as being HTLV-I/II seropositive. Seventeen recipients were seropositive, an apparent transmission rate of 12.8%. Red blood cells and platelets were the implicated components, and red blood cells that were less than 6 days old had a transmission efficiency of 80%. Virus typing enabled documentation of primary and secondary transfusion transmission of HTLV-I and HTLV-II, including the direct transmission of HTLV-II by a donor with a history of intravenous drug use. We conclude that transfusion transmission of HTLV-I/II to approximately 700 recipients per year occurred in the United States before routine donor testing began in 1988.

Human immunodeficiency virus infection and indeterminate western blot patterns. Prospective studies in a low prevalence population.

Interpretation of human immunodeficiency virus (HIV) antibody results that are "indeterminate" rather than clearly positive or negative is problematic for the person delivering the result as well as for the individual being tested. To improve counseling messages for these individuals, we evaluated data collected from a well-characterized cohort of 387 blood donors who had been monitored for up to 2 years. We sought to determine if persons with indeterminate Western blot patterns were infected with HIV, and whether information derived from follow-up monitoring would assist in the development of counseling messages for persons on whom no follow-up information was available. Donors were studied by laboratory assays, clinical evaluation, and assessment of risk for HIV. The absence of HIV infection in 97 of 98 donors with indeterminate Western blot patterns was confirmed by clinical follow-up, Western blot assays of sequential samples, and negative gene amplification results. We propose supplemental guidelines to be used as an adjunct to existing interpretive criteria for counseling individuals when they first present with an indeterminate Western blot finding.

Are outcomes the same with all dry powder inhalers?

Most clinicians and patients would intuitively say that the inhaler device used influences the outcome achieved in asthma. However, it is important to have objective evidence to support or refute this view. Systematic reviews have suggested that there is no difference in clinical effectiveness between dry powder inhalers and metered-dose inhalers. However, the studies included in the review were randomised clinical trials and not studies based on real-life clinical practice. In the real world, the efficacy of products as determined in a specified and well-monitored population is only one aspect of product performance--patient characteristics and behaviour are critical. Observational studies in real-world primary care settings suggest that the choice of inhaler device has an important impact on asthma outcomes. The IMS Mediplus database has now been used to compare outcomes among patients receiving initial maintenance therapy with beclometasone dipropionate administered via different dry powder inhalers. Patients using the DISKHALER dry powder inhaler used significantly less short-acting beta(2)-agonist than those using the ROTAHALER dry powder inhaler. This suggests a difference in the level of asthma control with the different devices, even when the same chemical entity is delivered. Real-world studies suggest, therefore, that outcomes are not always the same with all dry powder inhalers. This indicates the need for further studies to investigate the impact of inhaler device choice and the impact of switching between devices.

Agreement between prospective diary data and retrospective questionnaire report of abdominal pain and stooling symptoms in children with irritable bowel syndrome.

BACKGROUND: In functional gastrointestinal disorders, patient recall of symptoms drives diagnostic decisions and evaluation of treatment response, and research conclusions about potential treatments. In pediatrics, parent report also impacts assessment and care. Hence, identifying methods for accurately capturing patient and parent report of irritable bowel syndrome (IBS) symptoms is important. This study evaluated correspondence between retrospective questionnaire (parent and child report) and prospective diary data for children and adolescents with IBS. METHODS: Participants included 50 children/adolescents with IBS per Rome III criteria. Children completed a 2-week pain and stool diary. Children and parents subsequently completed a 2-week recall questionnaire, reporting number of pain days, maximum pain, days without bowel movement, and days with diarrhea during the diary interval. Intraclass correlation coefficients and Bland-Altman plots assessed agreement. KEY RESULTS: For pain and days without bowel movement, overall agreement between child recall questionnaire and child diary was strong, although under conditions likely to facilitate agreement and with individual variation observed. Parent recall and child diary were less concordant, and agreement about diarrhea was poor for parent and child. Age did not significantly correlate with agreement. CONCLUSIONS & INFERENCES: Child questionnaire with short recall interval may be a reasonable approximation for diary data, although this varies by individual and replication/investigation of lengthier recall are needed. Relying on parent questionnaire does not appear a suitable proxy, and recall of stool form by both parent and child appears more problematic. These results combined with existing literature support use of diary data whenever possible.

Race/ethnicity as a risk factor for HIV-1 infection among Connecticut intravenous drug users.

This cross-sectional study of 341 entrants to drug abuse treatment in four Connecticut cities in 1986-1987 evaluated whether demographic, behavioral, viral serologic, or economic differences explained the disproportionate risk of human immunodeficiency virus type 1 (HIV-1) infection among black and Hispanic intravenous drug users (IVDUs), relative to non-Hispanic white IVDUs. Blacks [odds ratio (OR) = 9.0, 95% confidence interval (CI) = 5.1-15.9] and Hispanics (OR = 4.1, 95% CI = 1.9-8.8) were at increased risk of HIV-1 infection, relative to non-Hispanic whites. Those who lived closer to New York City, injected drugs more frequently, used intravenous drugs for a longer duration, used shooting galleries, had greater numbers of sexual partners, had human cytomegalovirus (CMV) or hepatitis B virus (HBV) antibodies, and had the lowest annual incomes were also at increased risk. However, none of these other factors accounted for the black and Hispanic HIV-1 risk in stratified analysis. Black race, Hispanic ethnicity, proximity to New York City, and number of drug injections in the past year each also remained significant, independent risk factors in a multivariate analysis. The increased HIV-1 risk of nonwhite IVDUs remained unexplained. Behavioral, sociologic, and/or biologic factors not identified in this study may modulate HIV-1 transmission dynamics in IVDUs.

Interrelationships between serologic markers of immune activation and T lymphocyte subsets in HIV infection.

Relationships among four serologic activation markers and T cell subsets were measured in HIV-seropositive former blood donors (N = 64) and seronegative controls (N = 61). Significant correlations were observed for the HIV group in pairwise comparisons of soluble IL-2 receptor (sIL-2R), beta 2-microglobulin (beta 2M), neopterin (NEOP), and soluble CD8 (sCD8). CD4 cell levels (number/microliter) in the HIV group showed significant negative correlation with all four serologic markers; CD8 cell levels, in contrast, showed no significant correlation with any serologic activation marker measured. Significant correlations were observed, however, among various cell surface activation markers and serologic activation markers. Specifically, the proportion of CD8 cells expressing CD45RA showed significant negative correlations with NEOP and B2M levels, whereas the proportion of CD8 cells expressing HLA-DR showed significant positive correlations with B2M and sIL-2R levels. Further, the proportion of CD8 cells expressing CD38 showed significant positive correlations with all four serologic activation markers. These findings indicate that sIL-2R, B2M, NEOP, and sCD8 show similar quantitative changes and correlational relationships to CD4 cell destruction in HIV infection; they differ, however, in their relationships to proportional changes in activated CD8 cell subsets.

Simian virus 40 and pleural mesothelioma in humans.

It has been reported that DNA of SV40, a virus of Asian macaques that is tumorigenic for rodents and can transform human cells in vitro, is present in pleural mesotheliomas and in several other cancers. To verify these observations, we tested paraffin sections from mesothelioma tissues of 50 patients for SV40 DNA using PCR with two separate sets of primers. The analytic sensitivity for detection of SV40 DNA was 1-10 genome copies. We also tested the specimens for beta-globin by PCR to assess the suitability of the specimen DNAs for amplification. beta-Globin amplification was detected in 48 of the 50 specimens, but SV40 DNA was not detected in any tumors, with either of two SV40 primer sets. Furthermore, sera from 34 additional patients with mesothelioma, 33 patients with osteosarcoma (another cancer reported to be SV40-related) and 35 controls were tested for SV40 antibodies by a plaque neutralization assay. The serological data, like the DNA results, did not support an association of SV40 with mesothelioma or with osteosarcoma; antibodies to SV40 were detected in three mesothelioma patients, in one osteosarcoma patient, and in one control. These findings call into question the association of SV40 with mesothelioma.

A comparison of the in vitro and in vivo thrombogenic activity of factor IX concentrates using stasis (Wessler) and non-stasis rabbit models.

The thrombogenic effects of selected factor IX concentrates were evaluated in two rabbit models; the Wessler stasis model and a novel non-stasis model. Concentrates active in either the NAPTT or TGt50 in vivo tests of potential thrombogenicity, or both, caused thrombus formation in the Wessler technique and activation of the coagulation system in the non-stasis model. A concentrate with low activity in both in vitro tests did not have thrombogenic effects in vivo, at the chosen dose. Results in the non-stasis model suggested that the thrombogenic effects of factor IX concentrates may occur by at least two mechanisms. A concentrate prepared from platelet-rich plasma and a pyrogenic concentrate were also tested and found to have no thrombogenic effect in vivo. These studies justify the use of the NAPTT and TGt50 in vitro tests for the screening of factor IX concentrates prior to clinical use.