Compound Muscle Action Potential Amplitude as a Predictor of Functional and Patient-Reported Outcomes in Ulnar Neuropathy at the Elbow.

BACKGROUND: Ulnar neuropathy at the elbow (UNE) is a debilitating upper extremity condition that often leaves patients with residual symptoms even after surgical treatment. The role of electrodiagnostic studies in guiding the treatment of UNE is not well established, and conventional electrodiagnostic parameters may not reflect the severity of disease. Compound muscle action potential (CMAP) amplitude is a parameter that corresponds with axonal injury and motor symptoms and may more accurately predict the severity of neurologic injury. METHODS: This prospective multicenter study recruited 78 patients in the Surgery of the Ulnar Nerve project. Patients underwent electrodiagnostic testing and clinical assessment of motor and sensory function, and completed patient-reported outcome questionnaires, including the Michigan Hand Outcome Questionnaire; the Disabilities of the Arm, Shoulder and Hand questionnaire; and the Carpal Tunnel Questionnaire (CTQ). Correlations were measured among each of the electrodiagnostic parameters and outcomes and predictive models for each outcome were subsequently developed. RESULTS: Of all the electrodiagnostic parameters measured, only CMAP amplitude was predictive of scores on the Michigan Hand Outcome Questionnaire; Disabilities of the Arm, Shoulder and Hand questionnaire; CTQ function scale, and motor impairment in grip and pinch strength. None of the parameters were predictive of scores on the CTQ symptom scale or sensory impairments as measured with two-point discrimination or Semmes-Weinstein monofilament testing. CONCLUSIONS: CMAP amplitude, but not other conventional electrodiagnostic parameters, is predictive of functional outcomes in UNE. This electrodiagnostic measurement can alert the clinician to severe cases of UNE and inform surgical decision-making. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Electrodiagnostic Predictors of Outcomes After In Situ Decompression of the Ulnar Nerve.

PURPOSE: Patients with severe ulnar neuropathy at the elbow frequently experience suboptimal surgical outcomes. Clinical symptoms alone may not accurately represent the severity of underlying nerve injury, calling for objective assessment tools, such as electrodiagnostic studies. The goal of our study was to determine whether specific electrodiagnostic parameters can be used to predict the outcomes after in situ decompression of the ulnar nerve. METHODS: This prospective study enrolled consecutive patients aged ≥18 years diagnosed with ulnar neuropathy at the elbow. Patients completed a baseline battery of motor, sensory, functional, and electrodiagnostic tests before undergoing in situ decompression of the ulnar nerve. They were reassessed at 6 weeks, 3 months, 6 months, and 12 months after surgery. Forty-two patients completed at least 2 follow-up assessments and were included in the study. RESULTS: When controlling for other electrodiagnostic measurements and demographic factors, none of the electrodiagnostic parameters were predictive of outcomes at 12 months after surgery. Patients with decreased compound muscle action potential amplitudes demonstrated slower trends of recovery in grip strength, pinch strength, and overall scores on the Michigan Hand Outcomes Questionnaire as well as its function, work, and activities of daily living subscales, Disabilities of the Arm, Shoulder, and Hand questionnaire, and the Carpal Tunnel Questionnaire. Decreased motor nerve conduction velocity was predictive of slower recovery of 2-point discrimination and pinch strength. CONCLUSIONS: Compound muscle action potential amplitude, but not other conventional electrodiagnostic parameters, was predictive of functional outcomes after in situ decompression of the ulnar nerve. This parameter should play a role in determining the timing and prognosis of treatment for ulnar neuropathy at the elbow. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

An Outcomes Study of Proximal Interphalangeal Joint Silicone Implant Arthroplasty Using the Volar Approach.

BACKGROUND: Arthroplasty is performed at the proximal interphalangeal joint for the management of disabling osteoarthritis. This prospective cohort study evaluated outcomes of the silicone implant for the proximal interphalangeal joint using the volar approach. The authors hypothesize that the volar approach without extensor mechanism disruption will provide improved motion and maintain joint extension. METHODS: Consecutive candidates for proximal interphalangeal joint silicone implant arthroplasty using the volar approach were evaluated. The Michigan Hand Outcomes Questionnaire and functional measurements, including grip/pinch strength and arc of motion, were administered preoperatively and at 6 weeks and 3, 6, and 12 months postoperatively. RESULTS: Twenty-eight patients (35 joints) were included in the study. Eighteen patients (24 joints) were followed to 1 year postoperatively, with an entire cohort average of 10-month follow-up. Nineteen patients were white women, and the mean age was 64 years. The authors' hypothesis was supported by the results showing a mean gain in arc of motion of 7 degrees and a mean 5-degree extension lag improvement at 1 year. The mean postoperative arc of motion was 53 degrees with a 10-degree average extension lag. The median Michigan Hand Outcomes Questionnaire pain score improved from 70 (60 to 80) to 28 (5 to 45); scores also improved for each of the questionnaire domains. Median grip strength was unchanged. CONCLUSIONS: The volar approach to proximal interphalangeal joint arthroplasty is technically challenging but facilitates early aggressive rehabilitation. This is critical for providing improved flexion, especially in the ulnar digits without worsening extension lag. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Seven-Year Outcomes of the Silicone Arthroplasty in Rheumatoid Arthritis Prospective Cohort Study.

OBJECTIVE: Rheumatoid arthritis (RA) causes destruction of the metacarpophalangeal (MCP) joints, leading to hand deformities, pain, and loss of function. This study prospectively assessed long-term functional and health-related quality-of-life outcomes in RA patients with severe deformity at the MCP joints. METHODS: RA patients between ages 18 to 80 years with severe deformity at the MCP joints were referred to 1 of the 3 study sites. Subjects who elected to undergo silicone metacarpophalangeal joint arthroplasty (SMPA) while continuing with medical management were followed in the SMPA cohort. Subjects who elected to continue with medical management alone without surgery were followed in the non-SMPA cohort. Objective measurements included grip and pinch strength as well as arc of motion, ulnar drift, and extensor lag of the MCP joints. Patient-reported outcomes included the Michigan Hand Questionnaire (MHQ) and the Arthritis Impact Measurement Scales questionnaire. Radiographs of SMPA implants were assessed and graded as intact, deformed, or fractured. RESULTS: MHQ scores showed large improvements post-SMPA, and baseline-adjusted expected outcomes in the SMPA group were significantly better at year 7 in function, aesthetics, satisfaction, and overall score compared to non-SMPA. SMPA subjects did not improve in grip or pinch strength, but achieved significant improvement and maintained the improvement long term in ulnar drift and extensor lag. CONCLUSION: Benefits of the SMPA procedure are maintained over 7 years with low rates of implant fracture or deformity. Non-SMPA patients remained stable in their hand function over the 7-year study duration.

How Rheumatoid Arthritis Patients Make Decisions Regarding Hand Reconstruction: A Qualitative Study from the Silicone Arthroplasty in Rheumatoid Arthritis Project.

BACKGROUND: Previous studies have determined specific factors influencing patients with rheumatoid arthritis to choose to undergo reconstructive hand surgery. However, little is known about how rheumatoid arthritis patients are counseled by physicians regarding surgical options and the concerns that cause patients to decide not to undergo hand surgery reconstruction. The authors conducted a qualitative study to investigate the decision-making process rheumatoid arthritis patients undergo when deciding about surgical treatment, including the specific involvement from their physicians in the decision. METHODS: Participants were recruited from the ongoing international collaborative Silicone Arthroplasty in Rheumatoid Arthritis study. Twenty semistructured interviews were conducted, and data were analyzed using grounded theory methodology. RESULTS: Eight of the 11 participants that underwent metacarpophalangeal joint arthroplasty indicated that improving hand function was the primary reason they chose to undergo surgery. Four of these participants were concerned about the aesthetics of their hands, whereas five of the eight participants who discussed their reasoning for not undergoing surgery felt aesthetics was not a good enough reason to undergo surgery. Three participants indicated that a negative perception of hand surgery by their rheumatologists discouraged them from the procedure. Finally, most (14 of 18) participants chose to make the final decision about surgery without involvement from their physician. CONCLUSIONS: The decision of whether or not to undergo surgery can be personal, and patients may prefer to make the final decision independently. It is important that rheumatoid arthritis patients receive collaborative counseling from their rheumatologists and hand surgeons to ensure they are making a knowledgeable decision.

Relationship between Patient Expectations and Clinical Measures in Patients Undergoing Rheumatoid Hand Surgery from the Silicone Arthroplasty in Rheumatoid Arthritis (SARA) Study.

BACKGROUND: The purpose of this study was to evaluate the relationship between preoperative patient expectations and clinical measures in patients undergoing rheumatoid hand surgery. METHODS: Patients were recruited as a part of a larger prospective multicenter study to evaluate outcomes of silicone metacarpophalangeal joint arthroplasty (SMPA). Patients in the surgical cohort completed a baseline expectation questionnaire asking about expectations for function, work, pain, and aesthetics after SMPA. Responses were categorized into groups of low, middle, and high expectations for each domain and for cumulative expectations across all domains. Other study measurements were taken at baseline and 1 year, including the Michigan Hand Outcomes Questionnaire (MHQ) and objective clinical measurements (i.e., grip strength, pinch strength, the Jebsen-Taylor Hand Function Test, ulnar drift, and extensor lag). RESULTS: Preoperative expectations and clinical measures were complete for 59 patients at baseline and 45 patients at 1-year follow-up. Preoperative expectation level was related to baseline patient-reported domains of activities of daily living and hand satisfaction measured by the MHQ (p = 0.04 and p = 0.07, respectively). Patients had relatively similar satisfaction with hand function postoperatively regardless of preoperative expectation level. No consistent relationship was seen between preoperative expectations and objective measures at baseline and 1-year follow-up. CONCLUSIONS: High preoperative expectations were not a risk factor for dissatisfaction postoperatively. Preoperative expectation level may be considered for stratifying baseline patient-reported hand function in patients with similar objective hand function.

A 5-Year Cost-Effectiveness Analysis of Silicone Metacarpophalangeal Arthroplasty in Patients with Rheumatoid Arthritis.

BACKGROUND: There is a paucity of research evaluating the cost-effectiveness of surgical interventions for rheumatoid arthritis patients. Previous reports have challenged the sustainability of improved outcomes after silicone metacarpophalangeal arthroplasty. The authors conducted an economic evaluation of the long-term health outcomes after silicone metacarpophalangeal arthroplasty. METHODS: The authors performed a 5-year prospective cohort study of 170 patients with rheumatoid arthritis (73 surgical and 97 nonsurgical). Objective functional measurements and patient-rated outcomes using the Michigan Hand Outcomes Questionnaire and the Arthritis Impact Measurement Scale 2 were collected at 3 and 5 years. A cost-effectiveness analysis using direct costs from Medicare outpatient claims data (2006 to 2010) was performed to estimate the incremental cost-effectiveness ratios for both the Michigan and Arthritis Impact Measurement Scale 2 measurements. RESULTS: At 5 years, the authors observed a statistically significant difference in upper extremity outcomes (Michigan Hand Outcomes Questionnaire) between the two groups, with surgical patients having higher outcomes. Costs associated with improved outcomes 5 years after surgery were $787 to $1150 when measured by the Michigan Hand Outcomes Questionnaire and $49,843 to $149,530 when measured by the Arthritis Impact scale. The incremental cost-effectiveness ratios did not substantially increase with their observed surgical revision rate of 5.5 percent (approximately 4 percent increase in incremental cost-effectiveness ratio) or with previously published long-term revision rates of 6.2 percent (approximately 6 percent increase in incremental cost-effectiveness ratio). CONCLUSIONS: Short-term improvements in upper extremity outcomes after silicone metacarpophalangeal arthroplasty are maintained over the 5-year follow-up period. These outcomes are achieved at a relatively low cost, even with the addition of potential surgical complications.

Patient expectations and long-term outcomes in rheumatoid arthritis patients: results from the SARA (Silicone Arthroplasty in Rheumatoid Arthritis) study.

Little evidence exists to understand the influence of patient expectations on outcomes for silicone metacarpophalangeal arthroplasty (SMPA). The purpose of this paper is to compare long-term treatment outcome experiences regarding hand function/appearance for a surgical and nonsurgical cohort of rheumatoid arthritis (RA) patients and contrast them to expectations at baseline. This sample is part of a larger multicenter prospective cohort study of RA patients enrolled from 2004 to 2008. A total of 169 RA patients with severe deformities at the metacarpophalangeal (MCP) joints were recruited in the original study. Expectations for SMPA were collected at enrollment. A follow-up patient-reported questionnaire was completed at long-term follow-up. Baseline expectation questionnaires were collected from 137 patients, and follow-up data from 84 patients (average 6.7 years follow-up). At baseline, a significantly higher percent of patients who chose surgery expected to do "Anything I want" or "More activities than I do now" 1 year from enrollment than those who chose nonsurgical treatment. At follow-up, surgical patients remained more likely to indicate that they were currently able to do "Anything" or "More activities" than nonsurgical patients. A higher percentage of surgical patients were "very satisfied" or "quite satisfied" with their treatment compared to nonsurgical patients. RA subjects who chose SMPA reported greater expectations for surgery prior to surgery and also greater levels of hand function and satisfaction at long-term follow-up.

Predictors of functional outcomes after simple decompression for ulnar neuropathy at the elbow: a multicenter study by the SUN study group.

OBJECTIVE: To identify predictors of surgical outcome for ulnar neuropathy at the elbow (UNE). DESIGN: Prospective cohort followed for 1 year. SETTING: Clinics. PARTICIPANTS: Patients diagnosed with UNE (N=55). INTERVENTION: All subjects had simple decompression surgery. MAIN OUTCOME MEASURES: The primary outcome measure was patient-reported outcomes, such as overall hand function through the Michigan Hand Outcomes Questionnaire (MHQ). Predictors included age, duration of symptoms, disease severity, and motor conduction velocity across the elbow. RESULTS: Multiple regression models with change in the overall MHQ score as the dependent variable showed that at 3 months postoperative time, patients with <3 months duration of symptoms showed 12 points (95% confidence interval [CI], 0.9-23.5) greater improvement in MHQ scores than those with ≥3 months symptom duration. Less than 3 months of symptoms was again associated with 13 points (95% CI, 2.9-24) greater improvement in MHQ scores at 6 months postoperative, but it was no longer associated with better outcomes at 12 months. A worse baseline MHQ score was associated with significant improvement in MHQ scores at 3 months (coefficient, -0.38; 95% CI, -.67 to -.09), and baseline MHQ score was the only significant predictor of 12 month MHQ scores (coefficient, -.40; 95% CI, -.79 to -.01). CONCLUSIONS: Subjects with <3 months of symptoms and worse baseline MHQ scores showed significantly greater improvement in functional outcomes as reported by the MHQ. However, duration of symptoms was only predictive at 3 or 6 months because most patients recovered within 3 to 6 months after surgery.

The effect of swan neck and boutonniere deformities on the outcome of silicone metacarpophalangeal joint arthroplasty in rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis patients with swan neck deformities are postulated to have greater metacarpophalangeal joint arc of motion because of their need to flex the joint to make a fist, whereas the boutonniere deformity places the fingers into the flexed position, creating less demand on the joint for grip. This study analyzes the effect of these deformities on the joint's arc of motion and hand function. METHODS: The authors measured the metacarpophalangeal joint arc of motion in 73 surgical patients. Data were allocated into groups by finger and hand deformity. Linear regression models were used to analyze the effect of the deformity on the joint's arc of motion. Functional outcomes were measured by the Michigan Hand Outcomes Questionnaire and the Jebson-Taylor Test. RESULTS: Nineteen fingers had boutonniere deformity, 95 had swan neck deformities, and 178 had no deformity. The no-deformity group had the least arc of motion at baseline (16 degrees) compared with the boutonniere (26 degrees) and swan neck (26 degrees) groups. Mean arc of motion in the no-deformity group compared with the boutonniere group at baseline was statistically significant, but all groups had similar arc of motion at long-term follow-up. Only mean Jebson-Taylor Test scores at baseline between the boutonniere and no-deformity groups were significantly different. CONCLUSIONS: The results did not support the hypothesis that swan neck deformities have better arc of motion compared with boutonniere deformity. Boutonniere deformity has worse function at baseline, but there was no difference in function among groups at long-term follow-up.

An outcome study for ulnar neuropathy at the elbow: a multicenter study by the surgery for ulnar nerve (SUN) study group.

BACKGROUND: Many instruments have been developed to measure upper extremity disability, but few have been applied to ulnar neuropathy at the elbow (UNE). OBJECTIVE: We measured patient outcomes following ulnar nerve decompression to (1) identify the most appropriate outcomes tools for UNE and (2) to describe outcomes following ulnar nerve decompression. METHODS: Thirty-nine patients from 5 centers were followed prospectively after nerve decompression. Outcomes were measured preoperatively and at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Each patient completed the Michigan Hand Questionnaire (MHQ), Carpal Tunnel Questionnaire (CTQ), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaires. Grip, key-pinch strength, Semmes-Weinstein monofilament, and 2-point discrimination were measured. Construct validity was calculated by using Spearman correlation coefficients between questionnaire scores and physical and sensory measures. Responsiveness was assessed by standardized response means. RESULTS: Key-pinch (P = .008) and Semmes-Weinstein monofilament testing of the ulnar ring (P < .001) and small finger (radial: P = .004; ulnar: P < .001) improved following decompression. Two-point discrimination improved significantly across the radial (P = .009) and ulnar (P = .007) small finger. Improved symptoms and function were noted by the CTQ (preoperative CTQ symptom score 2.73 vs 1.90 postoperatively, P < .001), DASH (P < .001), and MHQ: function (P < .001), activities of daily living (P = .003), work (P = .006), pain (P < .001), and satisfaction (P < .001). All surveys demonstrated strong construct validity, defined by correlation with functional outcomes, but MHQ and CTQ symptom instruments demonstrated the highest responsiveness. CONCLUSION: Patient-reported outcomes improve following ulnar nerve decompression, including pain, function, and satisfaction. The MHQ and CTQ are more responsive than the DASH for isolated UNE treated with decompression.

Development of a brief, 12-item version of the Michigan Hand Questionnaire.

BACKGROUND: The Michigan Hand Questionnaire is one of the most widely used hand-specific surveys that measure health status relevant to patients with acute and chronic hand disorders. However, item redundancy exists in the original version, and an abbreviated survey could minimize responder burden and offer broader applicability. METHODS: Patients (n = 422) with four specific hand conditions--rheumatoid arthritis (n = 162), thumb carpometacarpal osteoarthritis (n = 31), carpal tunnel syndrome (n = 97), and distal radius fracture (n = 132)--completed the Michigan Hand Questionnaire at two time points. Correlation analysis identified two items from each of six domains (i.e., function, activities of daily living, work, pain, aesthetics, and satisfaction). The Brief Michigan Hand Questionnaire score was calculated as the sum of the responses to the 12 items. Psychometric analysis was performed to describe the reliability, validity, and responsiveness of the Brief Michigan Hand Questionnaire. RESULTS: The Brief Michigan Hand Questionnaire includes 12 items that were highly correlated with the summary Michigan Hand Questionnaire score (r = 0.99, p < 0.001). The Brief Michigan Hand Questionnaire scores were highly correlated between the two time periods (r = 0.78, p < 0.001) and by disease type. Responsiveness of the Brief Michigan Hand Questionnaire was high for all diseases and similar to that of the original Michigan Hand Questionnaire. CONCLUSIONS: The 12-item Brief Michigan Hand Questionnaire is an efficient and versatile outcomes instrument specific to hand disability that retains the psychometric properties of the original Michigan Hand Questionnaire. The Brief Michigan Hand Questionnaire is an important tool with which to measure patient outcomes and the quality of care in hand surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, I.(Figure is included in full-text article.).

Developing good clinical questions and finding the best evidence to answer those questions.

Evidence-based medicine involves the integration of the best scientific evidence available with physician experience and patient preferences. One of the first steps in evidence-based medicine involves developing a question based on issues encountered with patients or a disease and finding evidence to answer the question. This article is a guide to plastic surgeons in how to begin the practice of evidence-based medicine by developing clinical questions and finding evidence to answer these questions.

A multicenter clinical trial in rheumatoid arthritis comparing silicone metacarpophalangeal joint arthroplasty with medical treatment.

PURPOSE: Metacarpophalangeal (MCP) joint deformities caused by rheumatoid arthritis can be treated using silicone metacarpophalangeal joint arthroplasty (SMPA). There is no consensus as to whether this surgical procedure is beneficial. The purpose of the study was to prospectively compare outcomes for a surgical and a nonsurgical cohort of rheumatoid arthritis patients. METHODS: The prospective study was conducted from January 2004 to May 2008 at 3 referral centers in the United States and England. Over a 3-year period, 70 surgical and 93 nonsurgical patients were recruited. One year data are available for 45 cases and 72 controls. All patients had severe ulnar drift and/or extensor lag of the fingers at the MCP joints. The patients all had 1-year follow-up evaluations. Patients could elect to have SMPA and medical therapy or medical therapy alone. Outcomes included the Michigan Hand Outcomes Questionnaire (MHQ), Arthritis Impact Measurement Scales, grip and pinch strength, Jebson-Taylor test, and ulnar deviation and extensor lag measurements at the MCP joints. RESULTS: There was no difference in the mean age for the surgical group (60) when compared to the nonsurgical group (62). There was also no significant difference in race, education, and income between the 2 groups. At 1-year follow-up, the mean overall MHQ score showed significant improvement in the surgical group but no change in the nonsurgical group, despite worse MHQ function at baseline in the surgical group. Ulnar deviation and extensor lag improved significantly in the surgical group, but the mean Arthritis Impact Measurement Scales scores and grip and pinch strength showed no significant improvement. CONCLUSIONS: This prospective study demonstrated significant improvement for RA patients with poor baseline functioning treated with SMPA. The nonsurgical group had better MHQ scores at baseline, and their function did not deteriorate during the 1-year follow-up interval.

A guide to planning and executing a surgical randomized controlled trial.

Evidence-based medicine requires that treatments given to patients demonstrate effectiveness. The randomized controlled trial (RCT) has become the preeminent study design to assess the efficacy of treatments. Randomized controlled trials are frequently used to evaluate pharmaceutical treatments but are less often used in surgery. The lack of surgical RCTs is partly due to ethical and methodological concerns associated with surgical interventions. We provide a guide to planning and conducting a surgical RCT.

The outcomes of outcome studies in plastic surgery: a systematic review of 17 years of plastic surgery research.

BACKGROUND: The authors assessed the state of outcomes studies in plastic surgery since the initiation of the modern outcomes movement in 1988 and propose future research directions. METHODS: A systematic review of health outcomes research in plastic surgery was conducted. Studies were extracted from the journals Plastic and Reconstructive Surgery and Annals of Plastic Surgery from 1988 to 2004, yielding 3520 articles, 1670 of which did not meet the inclusion criteria; thus, 1850 articles were reviewed. Studies were analyzed with respect to topic of interest, category of outcome study, study design, endpoint of results, and level of impact on health outcomes, rated on a scale of 1 to 4 using a revised version of the Agency for Healthcare Research and Quality's outcomes impact scale. A level 4 study demonstrates the greatest direct impact on patient outcomes. RESULTS: Ninety percent of studies had a level 1 impact; 10 percent had a level 4 impact. Breast surgery was most represented, constituting 26 percent of studies. Morbidity and objective clinical outcomes were the most frequent endpoints, cited in 52 percent and 32 percent of studies, respectively. Economic analyses were the least frequently encountered outcome study category, represented in only 0.6 percent of studies. CONCLUSIONS: Most studies in this review had a level 1 impact, signifying that most outcomes studies in plastic surgery do not show a direct policy impact in patient outcomes. However, they are important in confirming the effectiveness of interventions already in clinical practice and raising new research questions. There is a need for more economic analysis research in plastic surgery outcomes studies.

A practical guide to meta-analysis.

The wealth of medical research published on a yearly basis demands methods to summarize the literature. Narrative or expert reviews were the traditional method to provide this summary; however, biases associated with narrative reviews raise questions regarding whether this process provides sufficient evidence to guide practice. Meta-analysis is becoming increasingly popular because it can combine results from similar studies to calculate an overall estimate of a treatment effect. Although meta-analysis has its limitations, a thoughtful and well-planned analysis is a valuable tool in providing a high level of evidence. We discuss the steps needed to perform a meta-analysis as a guideline for those interested in pursuing this type of research.