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Blair H Smith

Publications and source records attributed to Blair H Smith.

At least 19 recordsLinked to original sources
PubMed2026

Assessment of blinding in pharmacotherapy and noninvasive neuromodulation randomized controlled trials for neuropathic pain in adults.

In randomized controlled trials (RCTs), study participants and research personnel are often blinded to minimize biases related to knowing treatment allocation. To determine if blinding was effective, participants may be asked which treatment they believe they received ("treatment guess"). This descriptive review characterized blinding assessment (BA) reporting in pharmacotherapy and neuromodulation neuropathic pain RCTs. Of 288 papers, 36 (12.5%) reported a BA. One paper reported the results of 2 studies, so in total 37 studies with a BA were assessed. Of these, 19 were crossover, 17 parallel, and 1 partial crossover in design. All 37 studies assessed participant blinding, and 10 also assessed investigator blinding. Approximately 27% included an "unsure" answer option for treatment guess, and 38% asked the reason for the guess. There were no clear patterns in BA reporting across time nor based on treatment type. Seventeen trials provided sufficient data to calculate Bang Blinding Index (BI) to determine blinding success. Participants remained blinded (BI = 0 &#xb1; 0.2) in 10/17 placebo and 10/17 treatment arms, 6 placebo and 5 treatment arms had a BI > 0.2 suggesting possible unblinding, whereas 1 placebo and 2 treatment arms had a BI < -0.2 suggesting misinformed guessing. Overall, we found that BAs are done in a minority of published neuropathic pain trials and with variable methodology. Given the importance of minimizing risk of bias because of treatment unblinding, future studies should consider including BAs, and further consensus building is necessary to determine if and how BAs should be conducted and interpreted in analgesic clinical trials.

Bias↗
PubMed2006

Symptom experience and subsequent mortality: results from the West of Scotland Twenty-07 study.

BACKGROUND: Associations between symptom experience and mortality have rarely been investigated. One study has suggested that the number of symptoms people experience may be an important predictor of mortality. This novel and potentially important finding may have important implications but needs to be tested in other cohorts. METHODS: 858 people aged around 58 years were interviewed by nurses in 1990/1 as part of the West of Scotland Twenty-07 Study. They were asked about the presence of symptoms in the last month from a checklist of 33 symptoms. Measures of morbidity included symptom type (respiratory, musculoskeletal, gastrointestinal, mental health, neurological, systemic) and symptom summary measures looking at the number and impact of symptoms (total number; number participants tended to have; number participants did not tend to have; number which restricted usual activities; number which led to GP consultation). Hazard ratios for thirteen-year all-cause mortality were calculated for symptom types, symptom summary measures, and self-assessed health with and without adjustment. RESULTS: On unadjusted analysis, and after adjusting for gender, socio-economic status and smoking, mortality was elevated in individuals reporting respiratory, systemic and mental health symptoms. After additional adjustment for chronic conditions and self-assessed health, only the association between mental health symptoms and mortality remained significant. On unadjusted analysis, and after adjusting for gender, socio-economic status and smoking, mortality was elevated in individuals with many (> or = 6) symptoms in four of the symptom summary measures examined. These relationships were no longer significant after additional adjustment for chronic conditions and self-assessed health. A clear trend of increasing mortality as self-assessed health became poorer was observed. This pattern remained statistically significant after adjustment for gender, socio-economic status, smoking, chronic conditions and the total number of symptoms experienced. CONCLUSION: Symptoms often thought of as minor may have important consequences later in life especially for those reporting mental health-related symptoms or those experiencing many symptoms. In this study however, self-assessed health appeared to be a better predictor of mortality than the type or number of symptoms experienced, even when the tendency to have and impact of the symptoms were taken into account.

Attitude to Health↗
PubMed2006

Generation Scotland: the Scottish Family Health Study; a new resource for researching genes and heritability.

BACKGROUND: Generation Scotland: the Scottish Family Health Study aims to identify genetic variants accounting for variation in levels of quantitative traits underlying the major common complex diseases (such as cardiovascular disease, cognitive decline, mental illness) in Scotland. METHODS/DESIGN: Generation Scotland will recruit a family-based cohort of up to 50,000 individuals (comprising siblings and parent-offspring groups) across Scotland. It will be a six-year programme, beginning in Glasgow and Tayside in the first two years (Phase 1) before extending to other parts of Scotland in the remaining four years (Phase 2). In Phase 1, individuals aged between 35 and 55 years, living in the East and West of Scotland will be invited to participate, along with at least one (and preferably more) siblings and any other first degree relatives aged 18 or over. The total initial sample size will be 15,000 and it is planned that this will increase to 50,000 in Phase 2. All participants will be asked to contribute blood samples from which DNA will be extracted and stored for future investigation. The information from the DNA, along with answers to a life-style and medical history questionnaire, clinical and biochemical measurements taken at the time of donation, and subsequent health developments over the life course (traced through electronic health records) will be stored and used for research purposes. In addition, a detailed public consultation process will begin that will allow respondents' views to shape and develop the study. This is an important aspect to the research, and forms the continuation of a long-term parallel engagement process. DISCUSSION: As well as gene identification, the family-based study design will allow measurement of the heritability and familial aggregation of relevant quantitative traits, and the study of how genetic effects may vary by parent-of-origin. Long-term potential outcomes of this research include the targeting of disease prevention and treatment, and the development of screening tools based on the new genetic information. This study approach is complementary to other population-based genetic epidemiology studies, such as UK Biobank, which are established primarily to characterise genes and genetic risk in the population.

Adolescent↗
PubMed2006

Can pain can be more or less neuropathic? Comparison of symptom assessment tools with ratings of certainty by clinicians.

Chronic pain is generally regarded as being divided into two mutually exclusive pain mechanisms: nociceptive and neuropathic. Recently, this dichotomous approach has been questioned and a model of chronic pain being 'more or less neuropathic' has been suggested. To test whether such a spectrum exists, we examined responses by patients with chronic pain to validated neuropathic pain assessment tools and compared these with ratings of certainty about the neuropathic origin of pain by their specialist pain physicians. We examined 200 patients (100 each with nociceptive and neuropathic pain) and administered the self-complete Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS score) and the Neuropathic Pain Scale (NPS). Clinicians were asked to rate their certainty of the presence of neuropathic pain mechanisms on a 100 mm visual analogue scale (VAS) (0='not at all neuropathic in origin' to 100='completely neuropathic in origin'). The whole sample was divided into tertiles based on ascending ratings of diagnostic certainty by clinicians using the VAS and labelled 'unlikely', 'possible' and 'definite' neuropathic pain. There were significant differences in median S-LANSS and NPS composite scores between all tertile groups. There were also significant differences between many S-LANSS and NPS item scores between groups. We have shown that higher scores on both the S-LANSS and the NPS are indicative of greater clinician certainty of neuropathic pain mechanisms being present. These data support the theoretical construct that pain can be more or less neuropathic and that pain of predominantly neuropathic origin may be a useful clinical concept.

Chronic Disease↗
PubMed2006

The epidemiology of chronic pain of predominantly neuropathic origin. Results from a general population survey.

UNLABELLED: Progress in the understanding of chronic pain with neuropathic features has been hindered by a lack of epidemiologic research in the general population. The Leeds Assessment of Neuropathic Symptoms and Signs score (S-LANSS) was recently validated for use in postal surveys, making the identification of pain of predominantly neuropathic origin possible. Six family practices in 3 UK cities (Aberdeen, Leeds, and London) generated a total random sample of 6,000 adults. The mailed questionnaire included demographic items, chronic pain identification, and intensity questions, the S-LANSS, the Level of Expressed Needs questionnaire, and the Neuropathic Pain Scale. With a corrected response rate of 52%, the prevalence of any chronic pain was 48% and the prevalence of pain of predominantly neuropathic origin was 8%. Respondents with this chronic neuropathic pain were significantly more likely to be female, slightly older, no longer married, living in council rented accommodation, unable to work, have no educational qualifications, and be smokers than all other respondents. Multiple logistic regression modeling found that pain of predominantly neuropathic origin was independently associated with older age, gender, employment (being unable to work), and lower educational attainment. Respondents with this pain type also reported significantly greater pain intensity, higher scores on the NPS, higher levels of expressed need, and longer duration of pain. This is the first estimate of the prevalence and distribution of pain of predominantly neuropathic origin in the general population, using a previously validated and reliable data collection instrument. PERSPECTIVE: Chronic pain with neuropathic features appears to be more common in the general population than previously suggested. This type of pain is more severe than other chronic pain but distributed similarly throughout sociodemographic groups.

Adolescent↗
PubMed2006

Genetic epidemiology and primary care.

Large-scale, population-based studies of genetic epidemiology are under way or planned in several countries, including the UK. The results will have many implications for GPs and their patients. Primary care has much to contribute to this research, and basing genetic epidemiology studies in primary care will confer several advantages. These include enhanced public engagement, building on the personal relationships and trust that are at the core of primary care practice; methodological factors that will strengthen study design; and the potential of linkage of multiple datasets and between networks of research practices. Essential development work with primary care professionals and the public is, however, required for this to happen, and, if undertaken, this work will have the additional important benefit of increasing the uptake of new knowledge into general practice.

Epidemiology↗
PubMed2005

The use of medication for chronic pain in primary care, and the potential for intervention by a practice-based pharmacist.

BACKGROUND AND OBJECTIVES: The majority of people with chronic pain use analgesics regularly. Ensuring their safe and appropriate use is important. This study aimed to describe patterns of analgesic prescribing in one general practice, devise a method of identifying chronic pain patients from prescribing records, and assess prescribing recommendations made after a pharmacist-led review of analgesic prescribing and identify the proportion of these acted on by GPs. METHODS: Prescribing records in a practice of 6720 patients were searched and 678 patients were identified as receiving prescriptions for analgesics. 230 were invited to participate and sent a questionnaire, including questions about chronic pain severity, general health and medications used. This was repeated after six months. The pharmacist completed a detailed medication review using information from medical records, questionnaires and personal interviews. Prescribing recommendations were made to GPs. RESULTS: 192 recommendations about safe or appropriate prescribing were made for 86% of participants after records review, 56% being directly related to analgesic use. After 6 months all recommendations had been implemented in 77% of the patients. Few additional recommendations were made after interview. There was little or no relationship with changes in chronic pain severity or general or psychological health. CONCLUSIONS: We have demonstrated a method of identifying patients with chronic pain in primary care, and the feasibility and acceptability of a pharmacist-led intervention. This is of potential value in primary care, as relevant prescribing recommendations were made for most patients although further research is required to assess these.

Adult↗
PubMed2005

The 'number needed to sample' in primary care research. Comparison of two primary care sampling frames for chronic back pain.

BACKGROUND: Sampling for primary care research must strike a balance between efficiency and external validity. For most conditions, even a large population sample will yield a small number of cases, yet other sampling techniques risk problems with extrapolation of findings. OBJECTIVE: To compare the efficiency and external validity of two sampling methods for both an intervention study and epidemiological research in primary care--a convenience sample and a general population sample--comparing the response and follow-up rates, the demographic and clinical characteristics of each sample, and calculating the 'number needed to sample' (NNS) for a hypothetical randomized controlled trial. METHODS: In 1996, we selected two random samples of adults from 29 general practices in Grampian, for an epidemiological study of chronic pain. One sample of 4175 was identified by an electronic questionnaire that listed patients receiving regular analgesic prescriptions--the 'repeat prescription sample'. The other sample of 5036 was identified from all patients on practice lists--the 'general population sample'. Questionnaires, including demographic, pain and general health measures, were sent to all. A similar follow-up questionnaire was sent in 2000 to all those agreeing to participate in further research. We identified a potential group of subjects for a hypothetical trial in primary care based on a recently published trial (those aged 25-64, with severe chronic back pain, willing to participate in further research). RESULTS: The repeat prescription sample produced better response rates than the general sample overall (86% compared with 82%, P < 0.001), from both genders and from the oldest and youngest age groups. The NNS using convenience sampling was 10 for each member of the final potential trial sample, compared with 55 using general population sampling. There were important differences between the samples in age, marital and employment status, social class and educational level. However, among the potential trial sample, there were no demographic differences. Those from the repeat prescription sample had poorer indices than the general population sample in all pain and health measures. CONCLUSIONS: The repeat prescription sampling method was approximately five times more efficient than the general population method. However demographic and clinical differences in the repeat prescription sample might hamper extrapolation of findings to the general population, particularly in an epidemiological study, and demonstrate that simple comparison with age and gender of the target population is insufficient.

Adult↗
PubMed2005

The S-LANSS score for identifying pain of predominantly neuropathic origin: validation for use in clinical and postal research.

This article describes the development and validation of the S-LANSS score, a self-report version of the Leeds Assessment of Neuropathic Symptoms and Signs pain scale. The S-LANSS aims to identify pain of predominantly neuropathic origin, as distinct from nociceptive pain, without the need for clinical examination. Two hundred patients with chronic pain were asked to complete the S-LANSS unaided. A researcher then administered the S-LANSS scale and the Neuropathic Pain Scale (NPS) in interview format. An independent clinician determined the pain type (neuropathic versus nociceptive) and rated his or her certainty about diagnosis. The S-LANSS scale was also incorporated into a chronic pain questionnaire that was sent to 160 community patients and 150 newly referred patients waiting for pain clinic assessment. The S-LANSS scale correctly identified 75% of pain types when self-completed and 80% when used in interview format. Sensitivity for self-completed S-LANSS scores ranged from 74% to 78%, depending on the cutoff score. There were significant associations between NPS items and total score with S-LANSS score. In the postal survey, completed questionnaires were returned by 57% of patients (n = 174). Internal consistency and convergent validity of the survey S-LANSS scores were confirmed. The findings support the S-LANSS scale as a valid and reliable self-report instrument for identifying neuropathic pain and it is also acceptable for use in postal survey research. Establishing valid measures of symptoms and signs in neuropathic pain will allow standardized comparisons with other investigational measures. This might lead to new insights into the relationship between pathophysiologic mechanisms and clinical manifestations of pain.

Chronic Disease↗
PubMed2004

Factors related to the onset and persistence of chronic back pain in the community: results from a general population follow-up study.

INTRODUCTION: We compared the prevalence of chronic back pain (CBP) at two points 4 years apart and examined socio-demographic, health, and pain-related factors associated with its onset and persistence. METHOD: A random population sample of 2,184 adults was surveyed in 1996 and resurveyed in 2000. The questionnaire included chronic pain case definition questions (pain for 3 months or longer); the cause (1996) or site (2000) of any chronic pain; the Chronic Pain Grade questionnaire; the Level of Expressed Need (LEN) questionnaire; the SF-36 general health questionnaire; and demographic questions. Those with CBP in 1996 and 2000 had "persistent" CBP; those with CBP in 1996 but not 2000 had "recovered" CBP; those with CBP in 2000 but not 1996 had "new" CBP. RESULTS: Corrected response rates were 82.3% (1996) and 83.0% (2000). The sample prevalence of CBP was 16% (1996) and 27% (2000). Factors in 1996 independently associated with "persistent" compared with "recovered" CBP were preexisting arthritis, high LEN, poor mental health, and not living alone. Factors independently predicting "new" CBP compared with no previous CBP were previous chronic pain elsewhere and poor physical health. "Persistent" CBP was associated with more severe pain, higher LEN, and poorer general health than "new" CBP. DISCUSSION: CBP is a common and lasting problem, whose persistence and onset are predicted by clinical (especially pain) and help-seeking behavior factors, rather than socio-demographic. Prevention should focus on these factors.

Adult↗
PubMed2004

Is chronic pain a distinct diagnosis in primary care? Evidence arising from the Royal College of General Practitioners' Oral Contraception study.

BACKGROUND: and Objectives. There is a case for considering chronic pain as a distinct diagnosis in primary care, independent of its cause or body site, to allow development of common management strategies. This study examined the prevalence and factors associated with chronic pain among women still in the Royal College of General Practitioners' Oral Contraception Study, and compared the factors associated with chronic pain arising at different body sites, to examine the support for this case. METHODS: A survey of 11797 women examined the presence and site(s) of chronic pain, and other health factors. Socio-demographic factors, attendance at the family doctor for the pain and self-rated health were examined for their association with any chronic pain and site-specific chronic pain. RESULTS: Thirty-eight percent of women reported any chronic pain, for which most had attended their family doctor. Manual social class, former oral contraceptive use and area of residence were independently associated with any chronic pain. Chronic pain at different sites was associated with different socio-demographic factors, and different proportions of women consulting their family doctor or reporting unfavourable health. These proportions rose with the number of reported sites of chronic pain. CONCLUSIONS: The findings confirm the high prevalence of chronic pain and its importance to primary care. They suggest that chronic pain occurrence at different body sites varies across population subgroups, with differences in its impact on health. These differences call into question the independence of a chronic pain diagnosis. However, other factors common to any chronic pain support the development of common management and prevention strategies in primary care, and the variations highlighted will inform the targeting of these. The number of sites of chronic pain may be more important than the actual site(s) in determining its impact.

Academies and Institutes↗
PubMed2004

Chronic pain and health status: how do those not using healthcare services fare?

Relatively little is known about the clinical importance of symptoms not presented to healthcare services. Using data from a community survey we examined the health status among those with chronic pain who reported using or not using healthcare services. Individuals with chronic pain who had used healthcare services in the previous year had poorer health than symptomatic responders who had not used services, irrespective of the severity of chronic pain. The findings suggest that there is little point in trying to detect and treat individuals not currently presenting to healthcare services with their pain.

Adult↗