Estimating the burden of disease in chronic pain with and without neuropathic characteristics: does the choice between the EQ-5D and SF-6D matter?

The EQ-5D and Short Form (SF)12 are widely used generic health-related quality of life (HRQoL) questionnaires. They can be used to derive health utility index scores, on a scale where 0 is equivalent to death and 1 represents full health, with scores less than zero representing states "worse than death." We compared EQ-5D or SF-6D health utility index scores in patients with no chronic pain, and chronic pain with and without neuropathic characteristics (NC), and to explore their discriminant ability for pain severity. Self-reported health and chronic pain status was collected as part of a UK general population survey (n=4451). We found moderate agreement between individual dimensions of EQ-5D and SF-6D, with most highly correlated dimensions found for mental health and anxiety/depression, role limitations and usual activities, and pain and pain/discomfort. Overall 43% reported full health on the EQ-5D, compared with only 4.2% on the SF-6D. There were significant differences in mean utilities for chronic pain with NC (EQ-5D 0.47 vs SF-6D 0.62) and especially for severe pain (EQ-5D 0.33 vs SF-6D 0.58). On the EQ-5D, 17% of those with chronic pain with NC and 3% without NC scored "worse than death," a state which is not possible using the SF-6D. Health utilities derived from EQ-5D and SF-12/36 can discriminate between group differences for chronic pain with and without NC and greater pain severity. However, the instruments generate widely differing HRQoL scores for the same patient groups. The choice between using the EQ-5D or SF-6D matters greatly when estimating the burden of disease

Clinical diagnostic model for sciatica developed in primary care patients with low back-related leg pain

Background Identification of sciatica may assist timely management but can be challenging in clinical practice. Diagnostic models to identify sciatica have mainly been developed in secondary care settings with conflicting reference standard selection. This study explores the challenges of reference standard selection and aims to ascertain which combination of clinical assessment items best identify sciatica in people seeking primary healthcare. Methods Data on 394 low back-related leg pain consulters were analysed. Potential sciatica indicators were seven clinical assessment items. Two reference standards were used: (i) high confidence sciatica clinical diagnosis; (ii) high confidence sciatica clinical diagnosis with confirmatory magnetic resonance imaging findings. Multivariable logistic regression models were produced for both reference standards. A tool predicting sciatica diagnosis in low back-related leg pain was derived. Latent class modelling explored the validity of the reference standard. Results Model (i) retained five items; model (ii) retained six items. Four items remained in both models: below knee pain, leg pain worse than back pain, positive neural tension tests and neurological deficit. Model (i) was well calibrated (p = 0.18), discrimination was area under the receiver operating characteristic curve (AUC) 0.95 (95% CI 0.93, 0.98). Model (ii) showed good discrimination (AUC 0.82; 0.78, 0.86) but poor calibration (p = 0.004). Bootstrapping revealed minimal overfitting in both models. Agreement between the two latent classes and clinical diagnosis groups defined by model (i) was substantial, and fair for model (ii). Conclusion Four clinical assessment items were common in both reference standard definitions of sciatica. A simple scoring tool for identifying sciatica was developed. These criteria could be used clinically and in research to improve accuracy of identification of this subgroup of back pain patients

Novel approach to characterising individuals with low back-related leg pain: cluster identification with latent class analysis and 12-month follow-up

Traditionally, low back-related leg pain (LBLP) is diagnosed clinically as referred leg pain or sciatica (nerve root involvement). However, within the spectrum of LBLP, we hypothesised that there may be other unrecognised patient subgroups. This study aimed to identify clusters of patients with LBLP using latent class analysis and describe their clinical course. The study population was 609 LBLP primary care consulters. Variables from clinical assessment were included in the latent class analysis. Characteristics of the statistically identified clusters were compared, and their clinical course over 1 year was described. A 5 cluster solution was optimal. Cluster 1 (n = 104) had mild leg pain severity and was considered to represent a referred leg pain group with no clinical signs, suggesting nerve root involvement (sciatica). Cluster 2 (n = 122), cluster 3 (n = 188), and cluster 4 (n = 69) had mild, moderate, and severe pain and disability, respectively, and response to clinical assessment items suggested categories of mild, moderate, and severe sciatica. Cluster 5 (n = 126) had high pain and disability, longer pain duration, and more comorbidities and was difficult to map to a clinical diagnosis. Most improvement for pain and disability was seen in the first 4 months for all clusters. At 12 months, the proportion of patients reporting recovery ranged from 27% for cluster 5 to 45% for cluster 2 (mild sciatica). This is the first study that empirically shows the variability in profile and clinical course of patients with LBLP including sciatica. More homogenous groups were identified, which could be considered in future clinical and research settings

Stratifying workers on sick leave due to musculoskeletal pain: Translation, cross-cultural adaptation and construct validity of the Norwegian Keele STarT MSK tool

ObjectivesStratified care using prognostic models to estimate the risk profiles of patients has been increasing. A refined version of the popular STarT Back tool, the Keele STarT MSK tool, is a newly developed model for matched treatment across a wide range of musculoskeletal pain presentations. The aim of this study was to translate and culturally adapt the Keele STarT MSK tool into Norwegian, examine its construct validity and assess the representativeness of the included sample.MethodsThe Keele STarT MSK tool was formally translated into Norwegian following a multistep approach of forward and backward translation. A pre-final version was tested in 42 patients. Minor changes were implemented. To assess its construct validity, an online survey was conducted among workers aged 18–67 years who were on sick leave (>4 weeks) due to musculoskeletal disorders. Construct validity was evaluated in terms of convergent and discriminant validity using Pearson’s correlation coefficient, and known-group validity by comparing risk subgroups as suggested by the COSMIN checklist. The representativeness of the sample was assessed by comparing demographic and sick leave information of participants to eligible non-participants (n=168,137).ResultsA representative sample of 549 workers participated in the validity assessment; 74 participants (13.5%) were categorised as low risk, 314 (57.2%) as medium risk and 161 (29.3%) as high risk. The construct validity was found sufficient, with 90.9% and 75.0% of the pre-defined hypotheses confirmed for convergent and discriminant validity, and known-group validity, respectively. Floor or ceiling effects were not found.ConclusionsThe Keele STarT MSK tool was successfully translated into Norwegian. The construct validity of the tool was acceptable in a representative cohort of workers on sick leave as a result of musculoskeletal pain. However, the analyses raised concerns as to whether one of the questions captures the construct it is intended to measure

HadISD: a quality-controlled global synoptic report database for selected variables at long-term stations from 1973--2011

[Abridged] This paper describes the creation of HadISD: an automatically quality-controlled synoptic resolution dataset of temperature, dewpoint temperature, sea-level pressure, wind speed, wind direction and cloud cover from global weather stations for 1973--2011. The full dataset consists of over 6000 stations, with 3427 long-term stations deemed to have sufficient sampling and quality for climate applications requiring sub-daily resolution. As with other surface datasets, coverage is heavily skewed towards Northern Hemisphere mid-latitudes. The dataset is constructed from a large pre-existing ASCII flatfile data bank that represents over a decade of substantial effort at data retrieval, reformatting and provision. These raw data have had varying levels of quality control applied to them by individual data providers. The work proceeded in several steps: merging stations with multiple reporting identifiers; reformatting to netCDF; quality control; and then filtering to form a final dataset. Particular attention has been paid to maintaining true extreme values where possible within an automated, objective process. Detailed validation has been performed on a subset of global stations and also on UK data using known extreme events to help finalise the QC tests. Further validation was performed on a selection of extreme events world-wide (Hurricane Katrina in 2005, the cold snap in Alaska in 1989 and heat waves in SE Australia in 2009). Although the filtering has removed the poorest station records, no attempt has been made to homogenise the data thus far. Hence non-climatic, time-varying errors may still exist in many of the individual station records and care is needed in inferring long-term trends from these data. A version-control system has been constructed for this dataset to allow for the clear documentation of any updates and corrections in the future.Comment: Published in Climate of the Past, www.clim-past.net/8/1649/2012/. 31 pages, 23 figures, 9 pages. For data see http://www.metoffice.gov.uk/hadobs/hadis

Repeated primary care consultations for non-specific physical symptoms in children in UK: a cohort study

BackgroundNon-specific physical symptoms (NSPS), such as headache and abdominal pain, are common reasons for children to consult primary care. NSPS represent a significant burden not only on society, but also on health care services, through frequent physician consultations and referrals to secondary care. Research evidence suggests a positive relationship between health and consulting behavior of parents and their children, but research on whether repeated physician consultations for NSPS in children is influenced by parental consultations for NSPS is lacking. The aim was to measure the frequency of repeated physician consultations for NSPS in children, and investigate whether this is influenced by maternal consultations for NSPS.MethodsA cohort study of children registered with primary care practices contributing to the Consultation in Primary Care Archive database. Participants were child-mother pairs registered between January 2007 and December 2010. The cohort comprised all children (n¿=¿1437) aged 2 to 16 years who consulted a physician for NSPS in 2009. Mothers¿ consultations for NSPS were measured between 2007 and 2008. Main outcome measures were repetition and frequency of consultations for NSPS in children (consultations for NSPS in both 2009 and 2010).ResultsOverall, 27% of children had repeated consultations for NSPS. The three most common repeated consultations were for back pain, constipation and abdominal pain. Exposure to maternal consultation NSPS was associated with 21% increase in consultation frequency for NSPS (adjusted incidence rate ratio 1.21; 95% CI 1.12, 1.31). After adjusting for child age and maternal age, maternal consultation for NSPS was associated with an increased risk of repeated consultations for NSPS in children (relative risk 1.41; 95% CI 1.16, 1.73). This association was also significant for specific NSPS groups including painful, gastrointestinal, and neurologic symptoms.ConclusionsRepeated consultation for NSPS is common among children. It is important for primary care physicians and secondary care clinicians, managing children referred from primary care for NSPS, to be aware that consultation for NSPS in mothers is a risk factor for repeated consultations for NSPS among children. More research is needed to uncover exactly how parental health influences health and consulting behavior of children

Sleep problems increase the risk of musculoskeletal pain in boys but not girls : a prospective cohort study

Adults with sleep problems are at higher risk for onset of musculoskeletal pain, but the evidence is less clear for children. This prospective cohort study investigated whether children with sleep problems are at higher risk for onset of musculoskeletal pain and explored whether sex is a modifier of this association. In a prospective cohort study of Australian schoolchildren (n = 1239, mean age 9 years), the associations between sleep problems at baseline and new onset of both musculoskeletal pain and persistent musculoskeletal pain (pain lasting > 3 months) 1 year later were investigated using logistic regression. The potential modifying effect of sex was also assessed. One-year incidence proportion for musculoskeletal pain onset is 43% and 7% for persistent musculoskeletal pain. Sleep problems were associated with musculoskeletal pain onset and persistent musculoskeletal pain onset in boys, odds ratio 2.80 (95% CI 1.39, 5.62) and OR 3.70 (1.30, 10.54), respectively, but not girls OR 0.58 (0.28, 1.19) and OR 1.43 (0.41, 4.95), respectively. Conclusions: Rates of musculoskeletal pain are high in children. Boys with sleep problems are at greater risk of onset of musculoskeletal pain, but girls do not appear to have higher risk. Consideration of sleep health may help prevent persistent musculoskeletal pain in children.What is Known:center dot Sleep problems are associated with the onset of musculoskeletal pain in adults.center dot It is not clear if the association between sleep problems and the onset of musculoskeletal pain is present also in children and if sex plays a role in this association.What is New:center dot This is the first large population-based study that has prospectively investigated the relationship between sleep problems and onset of musculoskeletal pain in school-aged children.center dot Children, especially boys with sleep problems, were at increased risk for the development of persistent musculoskeletal pain.Peer reviewe

Determining one-year trajectories of low back related leg pain in primary care patients: growth mixture modelling of a prospective cohort study

Objective The clinical presentation and outcome of patients with back and leg pain in primary care are heterogeneous and may be better understood by identification of homogeneous and clinically meaningful subgroups. Subgroups of patients with different back pain trajectories have been identified, but little is known about the trajectories for patients with back‐related leg pain. This study sought to identify distinct leg pain trajectories, and baseline characteristics associated with membership of each group, in primary care patients. Methods Monthly data on leg pain intensity were collected over 12 months for 609 patients participating in a prospective cohort study of adult patients seeking healthcare for low back and leg pain including sciatica, of any duration and severity, from their general practitioner. Growth mixture modelling was used to identify clusters of patients with distinct leg pain trajectories. Trajectories were characterised using baseline demographic and clinical examination data. Multinomial logistic regression was used to predict latent class‐membership with a range of covariates. Results Four clusters were identified: (1) improving mild pain (58%), (2) persistent moderate pain (26%), (3) persistent severe pain (13%), and (4) improving severe pain (3%). Clusters showed statistically significant differences with a number of baseline characteristics. Conclusion Four trajectories of leg pain were identified. Clusters 1, 2 and 3 were generally comparable to back pain trajectories, while cluster 4, with major improvement in pain, is infrequently identified. Awareness of such distinct patient groups improves understanding of the course of leg pain and may provide a basis of classification for intervention

Trends in long-term opioid prescribing in primary care patients with musculoskeletal conditions: an observational database study

Long-term opioids may benefit patients with chronic pain but have also been linked to harmful outcomes. In the United Kingdom, the predominant source of opioids is primary care prescription. The objective was to examine changes in the incidence, length, and opioid potency of long-term prescribing episodes for musculoskeletal conditions in UK primary care (2002-2013). This was an observational database study (Clinical Practice Research Datalink, 190 practices). Participants (=18 years) were prescribed an opioid for a musculoskeletal condition (no opioid prescribed in previous 6 months), and issued =2 opioid prescriptions within 90 days (long-term episode). Opioids were divided into short- and long-acting noncontrolled and controlled drugs. Annual incidence of long-term opioid episodes was determined, and for those still in a long-term episode, the percentage of patients prescribed each type 1 to 2 years, and >2 years after initiation. Annual denominator population varied from 1.25 to 1.38 m. A total of 76,416 patients started 1 long-term episode. Annual long-term episode incidence increased (2002-2009) by 38% (42.4-58.3 per 10,000 person-years), remaining stable to 2011, then decreasing slightly to 55.8/10,000 (2013). Patients prescribed long-acting controlled opioids within the first 90 days of long-term use increased from 2002 to 2013 (2.3%-9.9%). In those still in a long-term opioid episode (>2 years), long-acting controlled opioid prescribing increased from 3.5% to 22.6%. This study has uniquely shown an increase in prescribing long-term opioids to 2009, gradually decreasing from 2011 in the United Kingdom. The trend was towards increased prescribing of controlled long-acting opioids and earlier use. Further research into the risks and benefits of opioids is required

An examination of writing pauses in the handwriting of children with Developmental Coordination Disorder.

This article has been made available through the Brunel Open Access Publishing Fund.Difficulties with handwriting are reported as one of the main reasons for the referral of children with Developmental Coordination Disorder (DCD) to healthcare professionals. In a recent study we found that children with DCD produced less text than their typically developing (TD) peers and paused for 60% of a free-writing task. However, little is known about the nature of the pausing; whether they are long pauses possibly due to higher level processes of text generation or fatigue, or shorter pauses related to the movements between letters. This gap in the knowledge-base creates barriers to understanding the handwriting difficulties in children with DCD. The aim of this study was to characterise the pauses observed in the handwriting of English children with and without DCD. Twenty-eight 8-14 year-old children with a diagnosis of DCD participated in the study, with 28 TD age and gender matched controls. Participants completed the 10 min free-writing task from the Detailed Assessment of Speed of Handwriting (DASH) on a digitising writing tablet. The total overall percentage of pausing during the task was categorised into four pause time-frames, each derived from the literature on writing (250 ms to 2 s; 2-4 s; 4-10 s and >10 s). In addition, the location of the pauses was coded (within word/between word) to examine where the breakdown in the writing process occurred. The results indicated that the main group difference was driven by more pauses above 10 s in the DCD group. In addition, the DCD group paused more within words compared to TD peers, indicating a lack of automaticity in their handwriting. These findings may support the provision of additional time for children with DCD in written examinations. More importantly, they emphasise the need for intervention in children with DCD to promote the acquisition of efficient handwriting skill