Can the General Public Be a Proxy for an "At-Risk" Group in a Patient Preference Study? A Disease Prevention Example in Rheumatoid Arthritis.

BACKGROUND: When selecting samples for patient preference studies, it may be difficult or impractical to recruit participants who are eligible for a particular treatment decision. However, a general public sample may not be an appropriate proxy. OBJECTIVE: This study compares preferences for rheumatoid arthritis (RA) preventive treatments between members of the general public and first-degree relatives (FDRs) of confirmed RA patients to assess whether a sample of the general public can be used as a proxy for FDRs. METHODS: Participants were asked to imagine they were experiencing arthralgia and had screening tests indicating a 60% chance of developing RA within 2 yrs. Using a discrete choice experiment, participants were offered a series of choices between no treatment and 2 unlabeled hypothetical treatments to reduce the risk of RA. To assess data quality, time to complete survey sections and comprehension questions were assessed. A random parameter logit model was used to obtain attribute-level estimates, which were used to calculate relative importance, maximum acceptable risk (MAR), and market shares of hypothetical preventive treatments. RESULTS: The FDR sample (n = 298) spent more time completing the survey and performed better on comprehension questions compared with the general public sample (n = 982). The relative importance ranking was similar between the general public and FDR participant samples; however, other relative preference measures involving weights including MARs and market share differed between groups, with FDRs having numerically higher MARs. CONCLUSION: In the context of RA prevention, the general public (average risk) may be a reasonable proxy for a more at-risk sample (FDRs) for overall relative importance ranking but not weights. The rationale for a proxy sample should be clearly justified. HIGHLIGHTS: Participants from the general public were compared to first-degree relatives on their preferences for rheumatoid arthritis (RA) preventive treatments using a discrete choice experiment.Preferences were similar between groups in terms of the most important and least important attributes of preventive treatments, with effectiveness being the most important attribute. However, relative weights differed.Attention to the survey and predicted market shares of hypothetical RA preventive treatments differed between the general public and first-degree relatives.The general public may be a reasonable proxy for an at-risk group for patient preferences ranks but not weights in the disease prevention context; however, care should be taken in sample selection for patient preference studies when choosing nonpatients.

The Symptoms in Persons At Risk of Rheumatoid Arthritis (SPARRA) questionnaire: predicting clinical arthritis development.

OBJECTIVE: There is a need to better define symptom characteristics associated with arthritis development in individuals at risk of rheumatoid arthritis (RA). We investigated whether reported symptoms in at-risk individuals could predict arthritis development and whether predictive symptoms differed between seropositive and seronegative at-risk individuals. METHOD: At-risk individuals from four cohorts (Netherlands, UK, Sweden, and Switzerland) completed the Symptoms in Persons At Risk of Rheumatoid Arthritis (SPARRA) questionnaire. Participants had either (i) anti-citrullinated protein antibodies and/or rheumatoid factor, or (ii) relevant symptoms with or without RA antibodies. Follow up was ≥ 24 months or until clinical arthritis development. Stepwise forward selection created SPARRA prediction models for the combined group and for a seropositive subgroup. RESULTS: Of 214 participants, the mean age was 50 years, 67% were female, and 27% (n = 58) developed clinical arthritis after a median time of 7 months. Four symptoms predicted arthritis development: self-reported joint swelling, joint pain moving from side to side (combined group only), feeling pins and needles in the joints, and often feeling fatigued (predicting non-arthritis). CONCLUSION: Specific symptoms can provide useful information to estimate a person's RA risk. Differences in predictive symptoms between seropositive and seronegative at-risk individuals need to be further investigated. Future research is needed to determine whether changes in symptoms over time improve prediction and to determine the value of SPARRA in optimizing the selection of individuals who need to consult a rheumatologist.

Exploring preferences of at-risk individuals for preventive treatments for rheumatoid arthritis.

OBJECTIVE: Some immunomodulatory drugs have been shown to delay the onset of, or lower the risk of developing, rheumatoid arthritis (RA), if given to individuals at risk. Several trials are ongoing in this area; however, little evidence is currently available about the views of those at risk of RA regarding preventive treatment. METHOD: Three focus groups and three interviews explored factors that are relevant to first degree relatives (FDRs) of RA patients and members of the general public when considering taking preventive treatment for RA. The semi-structured qualitative interview prompts explored participant responses to hypothetical attributes of preventive RA medicines. Transcripts of focus group/interview proceedings were inductively coded and analysed using a framework approach. RESULTS: Twenty-one individuals (five FDRs, 16 members of the general public) took part in the study. Ten broad themes were identified describing factors that participants felt would influence their decisions about whether to take preventive treatment if they were at increased risk of RA. These related either directly to features of the specific treatment or to other factors, including personal characteristics, attitude towards taking medication, and an individual's actual risk of developing RA. CONCLUSION: This research highlights the importance of non-treatment factors in the decision-making process around preventive treatments, and will inform recruitment to clinical trials as well as information to support shared decision making by those considering preventive treatment. Studies of treatment preferences in individuals with a confirmed high risk of RA would further inform clinical trial design.

Detection and enumeration of Campylobacter jejuni and Campylobacter coli by indirect impedimetry with an oxygen scavenging system.

Six strains of Campylobacter jejuni and Campylobacter coli were shown to grow in a variety of media, but, with one exception, they were unable to produce sufficient change in the electrical properties of the medium to allow their detection by impedance monitoring. With the use of an indirect method based on absorption of evolved carbon dioxide and a medium containing the oxygen scavenger Oxyrase, all strains were detectable, and correlations between time to detection and the logarithm of the inoculum level were excellent. The level of interstrain variation was sufficiently low that all data could be consolidated into a single calibration curve (r = 0.987).

Creation and analysis of a computerized database of interventions to facilitate adult sleep.

BACKGROUND: Although sleep problems are a frequent complaint of ill and older adults, there is no ready source of continually updated scientific knowledge about sleep promotion interventions used by nurses. OBJECTIVES: To create a database of sleep promotion research and to describe the nature and strength of studies about nursing interventions used to promote sleep in adults. METHODS: Computer, hand, ancestry, and author searches were used to identify nursing and related-discipline studies of sleep promotion in adults. An experimental software program, arcs, was used to store, retrieve, examine, and summarize sleep research findings. RESULTS: Twelve interventions within the basic scope of nursing practice were identified. All were nonpharmacologic. Interventions were grouped according to their presumed mechanism of action: 1) to relax the sleeper, 2) to manage noise, 3) to re-pattern the sleep-wake schedule, or 4) to inform the sleeper about sleep hygiene. CONCLUSIONS: The research base underpinning sleep promotion practices in nursing is sparse. The use of relaxation approaches to promote sleep in those with chronic insomnia has the most support. Extensive research involving other interventions and populations is needed. As more studies become available, they can be added to the computer database, thus facilitating dissemination of scientific knowledge to guide nursing practice.

The use of the arcs software system to store and examine sleep research results.

Ready access to research results is essential if nurses are to keep current with the scientific knowledge available to guide practice. Sigma Theta Tau International has supported the development of a software system that facilitates ongoing storage of information from research reports and can be used to gain online access to continually updated databases of research results called "knowledgebases." One such experimental knowledgebase, the Sleep Promotion Knowledgebase, includes studies of correlates of poor sleep in adults as well as sleep interventions and outcomes. The authors describe the creation of the Sleep Promotion Knowledgebase using arcs BUILDER to store information about research reports and the scientific findings they contain. The use of arcs MAPPER to examine sleep promotion interventions also is described. The strengths and limitations of the software system are identified, and the potential uses of arcs to disseminate sleep research results are discussed.

Involvement of the cell envelope of Listeria monocytogenes in the acquisition of nisin resistance.

The involvement of the cell wall in the acquisition of nisin resistance by Listeria monocytogenes F6861 and its nisin-resistant mutant was investigated. Results indicated that without a cell wall, the acquired nisin resistance of the mutant was lost. Cell surface hydrophobicity was shown to correlate with nisin sensitivity; the wild type strain being more hydrophobic than its mutant. The possible role of S-layer proteins in nisin resistance was investigated. Examination of strains by freeze-etching and atomic force microscopy did not demonstrate the presence of S-layers in either strain while SDS-PAGE following S-layer extraction procedures revealed no major protein bands. Chloramphenicol did not adversely affect the frequency of isolation of nisin-resistant mutants, indicating that de novo protein synthesis was not involved. The involvement of other cell surface components, teichoic and lipoteichoic acids, was also examined. In contrast with other reports, comparison of the total phospholipid content of the mutant with its parental strain showed no significant difference (P > 0.05).

Cross-reactivity of bacteriocins from lactic acid bacteria and lantibiotics in a nisin bioassay and ELISA.

A number of bacteriocins from lactic acid bacteria and lantibiotics were tested for cross-reactivity in a nisin ELISA and bioassay. The bacteriocins showed no cross-reactivity, reflecting their structural dissimilarity from nisin. The lantibiotic subtilin which shares many common structural features with nisin, showed a high cross-reactivity in both the ELISA and the bioassay suggesting possible modifications to nisin to enhance its activity. Gallidermin did not cross react in the ELISA but did produce a zone of inhibition in the less specific bioassay. Other lantibiotics tested did not react in either assay.

A biomechanical investigation of short segment spinal fixation for burst fractures with varying degrees of posterior disruption.

A biomechanical study was performed to evaluate the effectiveness of the Fixateur Interne pedicle screw system and the Syracuse I-Plate anterior fixation system. A total of 12 fresh frozen cadaver spines were tested intact, after burst fracture was created and application of a fixation device (six each), and after six serial transections of posterior ligaments and bony structures. Spines were loaded to a maximum of 10 N-m in flexion, extension, left and right lateral bending, and clockwise and counter-clockwise rotation. Results indicate that both systems reduce spinal flexibility in flexion, extension, and lateral bend loading when used to reduce and fix a classic burst fracture without posterior disruption. No decrease in flexibility was found in axial rotation for either device. After transection of all posterior elements, the I-Plate construct became much more flexible than the intact spine in flexion, extension, and axial rotation loading. The internal fixator construct retained more stability than the I-Plate construct after transection of posterior elements in flexion and extension loading, but was considerably more flexible than the intact spine in axial rotation loading. The results imply that the posterior internal fixator provides much better stabilization than the anterior I-Plate for those cases in which there is a large amount of posterior disruption in addition to an anterior burst injury. Neither device provides extensive support in axial rotation loading.

Pyarthrosis of the knee. Treatment considerations.

Patients with pyarthrosis of the knee can be effectively managed by several different methods. A retrospective review of patients with the diagnosis of septic arthritis of the knee was undertaken to determine the efficacy of two different treatment programs. Multiple-needle arthrocentesis was contrasted with formal arthrotomy drainage. In this series, patients with a longer than three-day history of a knee pyarthrosis and those with Staphylococcus aureus or enteric gram-negative organisms on culture benefited from open drainage procedures in lieu of repeated aspiration techniques.

Traction force profiles associated with the use of a fracture table: a preliminary report.

A load cell was developed that can reliably monitor longitudinal traction forces applied to limbs during several different orthopaedic procedures. This permitted determination of tensile loads and the effects of patient limb positions on tension magnitudes. The relationships between the magnitude and duration of applied tension to functional nerve changes were also studied. This preliminary report reviews traction force data on seven patients for eight operations. Mean peak loads for femoral, tibial, and hip procedures were 686, 356, and 306 N, respectively. Adduction of the limb around a fixed peroneal post caused great increases in traction forces.

Skin protection during external fixation frame pin insertion: an alternative method.

Local skin necrosis and pin tract infections are common sequelae following the application of external fixation skeletal frames. Drill guides are effective instruments that help to minimize these problems. Standard nasal speculums are readily available in most operating rooms and can also be used to protect skin and soft tissues during pin insertion.

Mutants of translational components that alter reading frame by two steps forward or one step back.

External suppressors, sufS, of a -1 frameshift mutant cause ribosomes to shift into the -1 frame when reading the sequence CAG GGA GUG. The resulting product is not Gln-Gly-Val but Gln-Gly-Ser with Ser being encoded by the underlined AGU. The alleles investigated are approximately 2% efficient in causing frameshifting. Two other suppressors, hopR and hopE of the same -1 frameshift mutant, cause some ribosomes reading the sequence GUG UG to decode a single amino acid, Val, from the five nucleotides. The possibility is considered that peptidyl-tRNA(Val) dissociates from the mRNA, but re-pairs in a triplet manner after the mRNA slips forward by two bases.

Fracture of the polyethylene acetabular cup in total hip arthroplasties.

Fracture of the acetabular cup is an uncommon complication in total hip arthroplasties, with only six examples described in the orthopedic literature. A patient is presented to illustrate the plain radiographic findings of acetabular cup fracture and to discuss the possible mechanisms involved.

Resection arthroplasty as a salvage procedure for a knee with infection after a total arthroplasty.

Between 1970 and 1983, resection arthroplasty was done as a salvage procedure for twenty-eight knees (twenty-six patients) with infection after total arthroplasty. Eleven patients had multiarticular rheumatoid arthritis; fourteen, osteoarthritis; and one, multiarticular neuropathic arthropathy. Systemic signs of infection were eliminated in all patients and local signs, in 89 per cent of the patients. After resection arthroplasty alone, fifteen patients were able to walk independently. Six patients with monoarticular osteoarthritis who found the resection arthroplasty to be unacceptable had a successful secondary arthrodesis. In three patients a spontaneous bone fusion developed after the resection, with the knee in a good position. Two patients who were unable to walk before the resection arthroplasty were still unable to do so postoperatively. Neither the patient's disease nor the type of prosthesis that had been used was a reliable predictor of success of the resection arthroplasty. The patients who had had the most severe disability before the total knee arthroplasty were most likely to be satisfied. Patients who had had less disability were more likely to find the results of resection arthroplasty to be unsatisfactory.