Accounting for Endogeneity in Maintenance Decisions and Overlay Thickness in a Pavement-Roughness Deterioration Model

Pavement deterioration models are an important part of any pavement management system. Many of these models suffer from endogeneity bias because of the inclusion of independent variables correlated with unobserved factors, which are captured by the model's error terms. Examples of such endogenous variables include pavement overlay thickness and maintenance and rehabilitation activities, both of which are not randomly chosen but are in fact decision variables selected by pavement engineers based on field conditions. Inclusion of these variables in a pavement deterioration model can result in biased and inconsistent model parameter estimates, leading to incorrect insights. Previous research has shown that continuous endogenous variables, such as pavement overlay thickness, can be corrected using auxiliary models to replace the endogenous variable with an instrumented variable that has lower correlation with the unobserved error term. Discrete endogenous variables, such as the type of maintenance and rehabilitation activities, have been accounted for by modeling the likelihood of each potential outcome and developing individual deterioration models for each of the potential responses. This paper proposes an alternative approach to accommodate discrete endogenous variables-the selectivity correction method-that allows a single model to incorporate the impacts of all discrete choices. This approach is applied to develop a pavement-roughness progression model that incorporates both continuous and discrete endogenous variables using field data from Washington State. The result is a roughness progression model with consistent parameter estimates, which have more realistic values than those obtained in previous studies that used the same data

Hyperthyroidism as a late effect in childhood cancer survivors-an Adult Life after Childhood Cancer in Scandinavia (ALiCCS) study

Background: Hyperthyroidism is a rare disorder which may negatively affect health and quality of life. Its occurrence in childhood cancer survivors has not previously been investigated in detail. Material and methods: In the hospital registers of the five Nordic countries, 32,944 childhood cancer survivors and 212,675 population comparisons were followed for the diagnosis of hyperthyroidism. Hospitalisation rates, standardised hospitalisation rate ratios and absolute excess risks were calculated with 95% confidence intervals (CI). Results: Hyperthyroidism was diagnosed in 131 childhood cancer survivors, yielding an overall relative risk of 1.6 (95% CI: 1.3-1.9) compared with population comparisons. The risk was greatest 1-5 years after the diagnosis of cancer and in survivors of thyroid cancers, neuroblastomas, acute lymphoblastic leukaemia and Hodgkin lymphoma. Sixty-seven percent of survivors with hyperthyroidism had tumours located in the head, neck or upper body and half of survivors with hyperthyroidism were irradiated with 77% of them in the head and neck area. Conclusion: Childhood cancer survivors are at an increased risk of hyperthyroidism, potentially resulting in non-endocrine morbidity.Peer reviewe

Long-term inpatient disease burden in the Adult Life after Childhood Cancer in Scandinavia (ALiCCS) study : A cohort study of 21,297 childhood cancer survivors

Background Survivors of childhood cancer are at increased risk for a wide range of late effects. However, no large population-based studies have included the whole range of somatic diagnoses including subgroup diagnoses and all main types of childhood cancers. Therefore, we aimed to provide the most detailed overview of the long-term risk of hospitalisation in survivors of childhood cancer. Methods and findings From the national cancer registers of Denmark, Finland, Iceland, and Sweden, we identified 21,297 5-year survivors of childhood cancer diagnosed with cancer before the age of 20 years in the periods 1943-2008 in Denmark, 1971-2008 in Finland, 1955-2008 in Iceland, and 1958-2008 in Sweden. We randomly selected 152,231 population comparison individuals matched by age, sex, year, and country (or municipality in Sweden) from the national population registers. Using a cohort design, study participants were followed in the national hospital registers in Denmark, 1977-2010; Finland, 1975-2012; Iceland, 1999-2008; and Sweden, 1968-2009. Disease-specific hospitalisation rates in survivors and comparison individuals were used to calculate survivors' standardised hospitalisation rate ratios (RRs), absolute excess risks (AERs), and standardised bed day ratios (SBDRs) based on length of stay in hospital. We adjusted for sex, age, and year by indirect standardisation. During 336,554 person-years of follow-up (mean: 16 years; range: 0-42 years), childhood cancer survivors experienced 21,325 first hospitalisations for diseases in one or more of 120 disease categories (cancer recurrence not included), when 10,999 were expected, yielding an overall RR of 1.94 (95% confidence interval [95% CI] 1.91-1.97). The AER was 3,068 (2,980-3,156) per 100,000 person-years, meaning that for each additional year of follow-up, an average of 3 of 100 survivors were hospitalised for a new excess disease beyond the background rates. Approximately 50% of the excess hospitalisations were for diseases of the nervous system (19.1% of all excess hospitalisations), endocrine system (11.1%), digestive organs (10.5%), and respiratory system (10.0%). Survivors of all types of childhood cancer were at increased, persistent risk for subsequent hospitalisation, the highest risks being those of survivors of neuroblastoma (RR: 2.6 [2.4-2.8]; n = 876), hepatic tumours (RR: 2.5 [2.0-3.1]; n = 92), central nervous system tumours (RR: 2.4 [2.3-2.5]; n = 6,175), and Hodgkin lymphoma (RR: 2.4 [2.3-2.5]; n = 2,027). Survivors spent on average five times as many days in hospital as comparison individuals (SBDR: 4.96 [4.94-4.98]; n = 422,218). The analyses of bed days in hospital included new primary cancers and recurrences. Of the total 422,218 days survivors spent in hospital, 47% (197,596 bed days) were for new primary cancers and recurrences. Our study is likely to underestimate the absolute overall disease burden experienced by survivors, as less severe late effects are missed if they are treated sufficiently in the outpatient setting or in the primary health care system. Conclusions Childhood cancer survivors were at increased long-term risk for diseases requiring inpatient treatment even decades after their initial cancer. Health care providers who do not work in the area of late effects, especially those in primary health care, should be aware of this highly challenged group of patients in order to avoid or postpone hospitalisations by prevention, early detection, and appropriate treatments.Peer reviewe

Knowledge of risk factors, beliefs and practices of female healthcare professionals towards breast cancer in a tertiary institution in Lagos, Nigeria

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the leading female malignancy in Nigeria. Screening for early detection has led to reduction in mortality from the disease. It is known that attitudes of physicians and motivation by community nurses influence uptake of screening methods by women. This study aims to investigate knowledge of breast cancer risk factors, beliefs about treatment and practice of screening methods among a cohort of female healthcare professionals in Lagos, Nigeria.</p> <p>Methods</p> <p>A cross-sectional study was conducted using a self-administered questionnaire to assess the knowledge of breast cancer risk factors, beliefs about treatment and practice of screening methods among 207 female doctors, nurses and other healthcare professionals working in a university teaching hospital in Lagos, Nigeria. Stratified random sampling method was employed. Chi square test, analysis of variance and Mantel-Haenszel test were performed in data analysis using SPSS v10.0 and Epi Info version 6 statistical packages.</p> <p>Results</p> <p>Female doctors obtained a mean knowledge score of 74% and were the only professional group that had satisfactory knowledge of risk factors. Majority (86%) believed that early breast cancer is curable while half of participants believed that prayer can make breast cancer disappear from the affected breast. Eighty three percent practice breast self-examination (BSE) once a month and only 8% have ever had a mammogram. Age, knowledge of risk factors, profession and beliefs were not significantly associated with rate of BSE in this study.</p> <p>Conclusion</p> <p>Results from this study suggest the need for continuing medical education programmes aimed at improving knowledge of breast cancer among female healthcare providers other than doctors.</p

Probabilistic analysis of degradation of façade claddings using Markov chain models

In this study, the time-dependent stochastic degradation of three types of claddings is analysed. For this purpose, 203 fac¸ades with stone claddings(directly adhered to the substrate), 195 with adhered ceramic claddings and 220 with painted surfaces were analysed. All the fac¸ades are located in Lisbon, Portugal. Their degradation condition was assessed through an extensive field work. Based on the data gathered, Markov chains are used to predict the degradation of claddings and to understand, in some detail, how the characteristics of the claddings contribute to the overall degradation. The results show that the distance from the sea and exposure to damp are significant to the degradation of all types of cladding. The type and size of stone plates also influence the degradation of stone claddings. The exposure to wind-rain action has a high impact on the degradation of ceramic claddings. The models proposed provide useful information on the probability of failure of the claddings; these results are fundamental in the context of insurance policies and in the definition of building maintenance plans

MOBILE AND WEARABLE DEVICE FEATURES THAT MATTER IN PROMOTING PHYSICAL ACTIVITY

Background: As wearable sensors/devices become increasingly popular to promote physical activity (PA), research is needed to examine how and which components of these devices people use to increase their PA levels. Aims: (1) To assess usability and level of engagement with the Fitbit One and daily SMS-based prompts in a 6-week PA intervention, and (2) to examine whether use/ level of engagement with specific intervention components were associated with PA change. Methods: Data were analyzed from a randomized controlled trial that compared (1) a wearable sensor/ device (Fitbit One) plus SMS-based PA prompts, and (2) Fitbit One only, among overweight/ obese adults (N067). We calculated average scores from Likert-type response items that assessed usability and level of engagement with device features (e.g., tracker, website, mobile app, and SMS-based prompts), and assessed whether such factors were associated with change in steps/day (using Actigraph GT3X&apos;). Results: Participants reported the Fitbit One was easy to use and the tracker helped to be more active. Those who used the Fitbit mobile app (36%) vs. those who did not (64%) had an increase in steps at 6-week follow-up, even after adjusting for previous web/app use: &apos;545 steps/ day (SE 0 265) vs. (28 steps/ day (SE 0242) (p 0.04). Conclusions: Level of engagement with the Fitbit One, particularly the mobile app, was associated with increased steps. Mobile apps can instantly display summaries of PA performance and could optimize self-regulation to activate change. More research is needed to determine whether such modalities might be cost-effective in future intervention research and practice

A nationwide study on reproductive function, ovarian reserve, and risk of premature menopause in female survivors of childhood cancer: design and methodological challenges

<p>Abstract</p> <p>Background</p> <p>Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly growing group of survivors. However, both chemo- and radiotherapy may adversely affect reproductive function. This paper describes the design and encountered methodological challenges of a nationwide study in the Netherlands investigating the effects of treatment on reproductive function, ovarian reserve, premature menopause and pregnancy outcomes in female childhood cancer survivors (CCS), the DCOG LATER-VEVO study.</p> <p>Methods</p> <p>The study is a retrospective cohort study consisting of two parts: a questionnaire assessing medical, menstrual, and obstetric history, and a clinical assessment evaluating ovarian and uterine function by hormonal analyses and transvaginal ultrasound measurements. The eligible study population consists of adult female 5-year survivors of childhood cancer treated in the Netherlands, whereas the control group consists of age-matched sisters of the participating CCS. To date, study invitations have been sent to 1611 CCS and 429 sister controls, of which 1215 (75%) and 333 (78%) have responded so far. Of these responders, the majority consented to participate in both parts of the study (53% vs. 65% for CCS and sister controls respectively). Several challenges were encountered involving the study population: dealing with bias due to the differences in characteristics of several types of (non-) participants and finding an adequately sized and well-matched control group. Moreover, the challenges related to the data collection process included: differences in response rates between web-based and paper-based questionnaires, validity of self-reported outcomes, interpretation of clinical measurements of women using hormonal contraceptives, and inter- and intra-observer variation of the ultrasound measurements.</p> <p>Discussion</p> <p>The DCOG LATER-VEVO study will provide valuable information about the reproductive potential of paediatric cancer patients as well as long-term survivors of childhood cancer. Other investigators planning to conduct large cohort studies on late effects may encounter similar challenges as those encountered during this study. The solutions to these challenges described in this paper may be useful to these investigators.</p> <p>Trial registration</p> <p>NTR2922; <url>http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2922</url></p

Childhood acute lymphoblastic leukemia in the Middle East and neighboring countries: A prospective multi-institutional international collaborative study (CALLME1) by the Middle East Childhood Cancer Alliance (MECCA)

Background: Little is known about childhood ALL in the Middle East. This study was undertaken by MECCA as initial efforts in collaborative data collection to provide clinical and demographic information on children with ALL in the Middle East. Procedure: Clinical and laboratory data for patients with ALL between January 2008 and April 2012 were prospectively collected from institutions in 14 Middle East countries and entered into a custom-built-database during induction phase. All laboratory studies including cytogenetics were done at local institutions. Results: The 1,171 voluntarily enrolled patients had a mean age of 6.1±3.9 years and 59.2 were boys. T-ALL represented 14.8 and 84.2 had B-precursor ALL. At diagnosis, 5.6 had CNS disease. The distribution of common genetic abnormalities reflected a similar percentage of hyperdiploidy (25.6), but a lower percentage of ETV6-RUNX1 translocation (14.7) compared to large series reported from Western populations. By clinical criteria, 47.1 were low/standard risk, 16.9 were intermediate risk, and 36 were high risk. Most patients received all their care at the same unit (96.9). Patients had excellent induction response to chemotherapy with an overall complete remission rate of 96. Induction toxicities were acceptable. Conclusions: This first collaborative study has established a process for prospective data collection and future multinational collaborative research in the Middle East. Despite the limitations of an incomplete population-based study, it provides the first comprehensive baseline data on clinical characteristics, laboratory evaluation, induction outcome, and toxicity. Further work is planned to uncover possible biologic differences of ALL in the region and to improve diagnosis and management. Pediatr Blood Cancer 2014; 61:1403-1410. © 2014 Wiley Periodicals, Inc

How do nurses and teachers perform breast self-examination: are they reliable sources of information?

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the most common cause of cancer-related deaths among women worldwide. The aim of the present study was to determine and compare knowledge, behavior and attitudes among female nurses and teachers concerning breast self-examination (BSE).</p> <p>Methods</p> <p>Two-hundred and eighty nine women working in Aydin, Turkey (125 nurses and 164 teachers) were included in the study. The data were collected using a questionnaire designed to measure the knowledge, attitudes and behavior of the groups. Analysis involved percentiles, χ²tests, <it>t </it>tests and factor analysis.</p> <p>Results</p> <p>The knowledge of nurses about BSE was higher than that of teachers (81.5% versus 45.1%; p < 0.001). BSE practice parameters (i.e. age groups, indications, frequency) were similar (p > 0.05), whereas skills in performing self-examination were higher in nurses (p < 0.001). Fear of having breast cancer is the most frequent reason for performing BSE. Among nurses, the reasons for failure to perform BSE were the absence of prominent breast problems (82%) and forgetting (56.4%). The teachers who did not perform BSE said that the reasons were lack of knowledge on how to perform self-examination (68.9%) and absence of problems (54%). Both groups had unacceptable technical errors in the performance of BSE.</p> <p>Conclusion</p> <p>We conclude that nurses and teachers should be supported with information enabling them to accomplish their roles in the community. To improve BSE practice, it is crucial to coordinate continuous and planned education.</p