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At least 91 records · Page 5Linked to original sources

PubMed2000

The rating scale preference measure as an evaluative measure in systemic lupus erythematosus.

Preference measures may be useful tools to assess patients' overall health-related quality of life. We studied the validity and sensitivity to change of the rating scale preference measure in patients with systemic lupus erythematosus (SLE), and compared its properties with those of the patient global assessment of SLE activity, in a prospective longitudinal observational study of changes in the symptoms and clinical disease activity of 23 patients. Patients were assessed every two weeks for up to 40 weeks. Construct validity was assessed by the strength of correlations between changes over time in the rating scale preference measure and patient global assessment and changes in the physician global assessment, Systemic Lupus Activity Measure (SLAM), European Consensus Lupus Activity Measure (ECLAM), the British Isles Lupus Assessment Group index (BILAG), and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Changes in the rating scale were more highly correlated with changes in each of these standards than were changes in the patient global assessment, demonstrating the construct validity of this measure. Sensitivity to change was measured using the two-week interval of greatest change in either the physician global assessment or the SLE activity measures as standards. The rating scale preference measure was less sensitive to change than the patient global assessment when tested against four different standards. The sensitivity to change of the rating scale was less than one-half that of the patient global assessment when either the SLAM or ECLAM was used as the standard. Although these results support the validity of the rating scale as a measure of health-related quality of life in patients with SLE, its limited sensitivity to change may make it less attractive as an endpoint measure in clinical trials.

Adult↗

PubMed2000

Measurement variability associated with KXRF bone lead measurement in young adults.

In vivo bone lead measurement using K X-ray fluorescence (KXRF) has been used to estimate long-term lead exposure, especially in adults. Relatively few studies have been conducted on young subjects with this technique. To explore the measurement variability of KXRF bone lead measurements in young subjects, the tibiae of two male cadavers from Boston, Massachusetts, 17 and 20 years of age, were obtained for repeated bone lead measurements. Bone lead concentrations were measured using a grid of nine locations, 1 cm apart, centered at the midpoint of the tibia. Each location was sampled using five 60-min measurements. Measured concentrations ranged from < 0 to 11.8 microg Pb/g bone mineral across a tibia with mean concentrations for the midpoint locations of 0.8 microg Pb/g bone mineral SD = 2.5 and 2.0 microg Pb/g bone mineral (SD = 1.9) for the left and right legs of the younger subject and 3.6 microg Pb/g bone mineral (SD = 2.6) and 6.0 microg Pb/g bone mineral (SD = 3.3) for the left and right legs of the older subject. Although bone lead concentrations did not vary significantly by measurement location in an individual leg, reported measurement uncertainty increased significantly at locations that were 1 cm from the center of the tibia horizontally (p < 0.0001). Symmetry in bone lead concentration between legs was observed for the 17-year-old subject. Potential asymmetry between the left and right legs was suggested for the 20-year-old subject (p = 0.06). These data describe the degree of variability that may be associated with bone lead measurements of young subjects with low bone lead concentrations using a standard spot-source KXRF instrument. Because of the importance of conducting additional research on adolescent lead toxicity, further improvements to the precision of KXRF measurement are needed.

Adolescent↗

PubMed2000

[A new optoelectronic measuring device for assessment of leg circumference in comparison with manual measurement].

For compression treatment to be effective in patients with chronic venous insufficiency, it is vital that leg circumference be measured accurately. If compression stockings are custom fit and appropriate for the medical indications, patient compliance will be high. Exact measurements of circumference and length are prerequisites for a good fit. The aim of the present study was to compare an opto-electronic device for the contact-free measurement of calf circumference with the conventional manual method using a tape measure. We investigated the differences between the results obtained with the two methods, and also their reproducibility. Circumferences were measured at defined heights on an anatomically shaped non-yielding leg model and on the leg of a healthy volunteer by 10 different experimenters both with the tape measure and with the opto-electronic device. The calf circumferences measured manually with the tape measure varied significantly more than those measured opto-electronically, both in the leg model and in the leg of the volunteer. A systematic error in the opto-electronic method appears unlikely, since the manual measurements on the leg model were both larger and smaller than those obtained with the opto-electronic device. Reproducibility was exceptionally high with the opto-electronic device (standard deviation 0.11-0.42 cm). The opto-electronic method yields rapid accurate measurements of circumference with excellent intra- and inter-operator reproducibility.

Anthropometry↗

PubMed1991

[Only rectal temperature measurements are suitable for routine temperature measurement].

A new rapid electronic thermometer (V.C.T. TERUMO) has been introduced to Danish hospitals. Oral and rectal V.C.T. measurements were compared with rectal measurements with mercury thermometers. In addition, rectal V.C.T. measurements in the wards were compared with rectal measurements with mercury thermometers. A total of 91 patients participated in the investigation. The average differences between the electronic rectal and oral compared with recordings by mercury thermometers were found to be 0.02 degree C and 0.75 degree C, respectively, under optimal conditions for measurement while the corresponding scatters of difference in temperature were 0.17 degree C and 0.74 degree C, respectively. The average difference between rectal temperature measurements with mercury thermometers and rectal V.C.T. measurements carried out during daily routine circumstances was 0.08 degree C while the scatter of the difference in temperature was 0.26 degree C. It is concluded that rectal V.C.T. measurements are just as suitable as rectal measurements with mercury thermometers and employment of rectal V.C.T. thermometer measurements is recommended in the daily hospital routine. Employment of oral and axillary measurements is discussed and not recommended.

Adult↗

PubMed1990

[Three dimensional shape measurement of teeth. (5) On the measurement by the newly developed double sensor laser displacement meter].

A laser displacement meter equipped with two PSD (Position Sensitive Device) sensors located 45 symmetrical to the incident beam was developed to measure the three dimensional shape of a tooth with a higher efficiency and accuracy. This displacement meter enabled compensation of the data at the shaded points without the rotational measurement which could not be done by the former single sensor displacement meter. The output voltages on the declined plane measured by the two sensors were different on the complicatedly declined plane. in such a case, the output measured by the sensor which made a larger angle with the declined plane was adopted since it was affected less by the secondary scattering. All regions of the 6 molar were measured without errors, and the cusps and fissures of the occlusal plane were measured as precisely as by the single sensor displacement meter. The time required for the measurement was about 10 min, which was one third that required for the former single sensor displacement meter. For measurement of a crown abutment tooth with steeply inclined slope and margin, by the single sensor displacement meter, the tooth area had to divided into four parts by tilting and rotation on the gonio stage, and required about one and half hours. However, with the present displacement meter, only the measurements with tilting were required and the time was reduced to about 40 min. Besides, the data connection for CG was accomplished in about 5 min, and the complete data without errors and overlap could be saved. This data will be able to give the inner shape of a crown for machining by CAM technique. As mentioned, the newly developed double sensor laser displacement meter greatly simplified the procedure to measure the shape of a tooth and enabled measurements with high precision.

Crowns↗

PubMed1995

Intraobserver and interobserver variations in sonographic measurements of kidney size in adult volunteers. A comparison of linear measurements and volumetric estimates.

Estimation of renal size by sonography can be performed by measuring renal length, volume, cortical volume or cortical thickness. Observer variation in these measurements is an important factor, especially when repeated measurements are compared. This study was performed to examine the magnitude of intraobserver and interobserver variations for each of the above-mentioned measurements, and to find the measurement with the lowest observer variation. Sonographic measurements were performed by 3 observers on 18 adult volunteers. The standard deviation of the difference (SDD) between any 2 pairs of measurements was used as the indicator of the magnitude of the observer variation. Renal length measurement showed the lowest observer variation with a relative SDD of 4 to 5%. Measurement of cortical thickness showed the poorest reproducibility with a relative SDD of 18 to 23%, while volumetric estimations had a relative SDD of 14 to 17%. Renal length measurement should be preferred to renal volume estimation, especially when comparing repeated measurements.

Adult↗

PubMed1997

[Quantitative measurements of regional cerebral blood flow using technetium-99m-L,L-ECD SPECT activated with acetazolamide: fundamental study of measurement's accuracy, comparison with 123I-IMP ARG method].

We measured regional cerebral blood flow before and after acetazolamide administration using a serial noninvasive method with 99mTc-ECD developed by Matsuda and Takeuchi et al., and compared the accuracy of measured values with those obtained by the conventional 123I-IMP ARG method. When the regional cerebral blood flow was measured for 80 brain regions in 5 subjects without scatter correction, a differential of 0.5 +/- 8.4% was obtained between values measured before and after physiological saline administration as a placebo. A differential of -0.2 +/- 12.6% was obtained when the same regions were measured with scatter correction. These findings indicated that placebo administration did not affect measured values, regardless of whether scatter correction was performed. When 64 regions in 4 subjects at rest were measured on two successive days, a differential of -1.1 +/- 9.0% was obtained between the values measured on the two days. A differential of -4.0 +/- 11.7% was obtained for the same regions following acetazolamide administration. These findings showed that measurements were reproducible both when subjects were at rest and when they were administered acetazolamide. The above two methods were used for measurement of 80 brain regions in the same 5 subjects for comparison. Measurements of subjects at rest and with acetazolamide administration were performed on separate days. The regression line y = 0.99x + 1.47, r = 0.80, was obtained for the subjects at rest, and y = 0.86x + 7.76, with r = 0.76, for the subjects following acetazolamide administration. These findings demonstrated a good correlation between the values obtained using the two methods. The values obtained using the method of Matsuda and Takeuchi et al., before and after acetazolamide administration were thus consistent with those reported previously using the conventional method, and the former method proved to be both simple and reliable.

Acetazolamide↗

PubMedDate not supplied

Connecting stuttering management and measurement: I. Core speech measures of clinical process and outcome.

BACKGROUND: There will always be a place for stuttering treatments designed to eliminate or reduce stuttered speech. When those treatments are required, direct speech measures of treatment process and outcome are needed in clinical practice. AIMS: Based on the contents of published clinical trials of such treatments, three 'core' measures of treatment outcome are presented for consideration by clinicians: measures of stuttering rate, speech rate and speech naturaleness. MAIN CONTRIBUTION: In contrast to clinical trials, however, clinicians are at liberty to have as many outcome measures as thought necessary, and to design non-standard ones to suit their needs and those of their clients. In that context, the merits of severity ratings of stuttering are considered. It is argued that the prime source of guidance of suitable measures of treatment process are the manuals of the treatments that have figured in clinical trials. CONCLUSIONS: Although there are independent data sources that contradict the axiom that treatment outcomes should be measured beyond the clinic, it is argued that it is premature to dispense with beyond-clinic process outcome measures for clinical practice. It is argued that for clinicians who conduct treatments in non-research contexts, one pretreatment outcome measurement occasion is sufficient, along with post-treatment measures at each maintenance visit. More than anything else, the numerous advantages of severity ratings of stuttering facilitate clinical measurement of treatment outcome and treatment process in several settings and on several occasions.

Adolescent↗

PubMed1995

Which outcome measures should be used in rheumatoid arthritis clinical trials? Clinical and quality-of-life measures' responsiveness to treatment in a randomized controlled trial.

OBJECTIVE: To determine the discriminant validity of the core set of outcome measures proposed by the American College of Rheumatology (ACR) and the Outcome Measures in Clinical Trials (OMERACT) conference committee to be used in clinical trials of rheumatoid arthritis (RA). METHODS: Utilizing data from a multicenter randomized double-blind clinical trial of low-dose cyclosporine and placebo in RA, we estimated the relative efficiency (RE) of measures to detect a treatment effect (relative to tender joint count, which was assigned a value of 1). Four pain measures (10-cm visual analog scale [VAS], 5-point categorical scale, Health Assessment Questionnaire [HAQ] pain index, Arthritis Impact Measurement Scales [AIMS] pain score) and 3 quality-of-life measures (Problem Elicitation Technique [PET], HAQ, AIMS) were compared. RESULTS: Physician and patient global measures were the most responsive instruments, although neither was statistically superior to tender joint count. Swollen joint count, grip strength, pain measured on a 10-cm VAS, and functional status as measured by the PET and HAQ were all of intermediate responsiveness. Morning stiffness, 5-point pain scale, and erythrocyte sedimentation rate were the least responsive instruments. CONCLUSION: This study provides further evidence to support the core set of outcome measures proposed by the ACR and OMERACT:

Adolescent↗

PubMed2006

Dosimetric consideration of individual 125I source strength measurement and a large-scale comparison of that measured with a nominal value in permanent prostate implant brachytherapy.

PURPOSE: We investigated the difference between measured and manufacturer's nominal source strength in a large sample of a single model of (125)I seeds. Physical characteristics of single seed measurement by the well-type ionization chamber were also investigated to provide dosimetric data. MATERIALS AND METHODS: A well-type ionization chamber with a single seed holder was used to measure source strength of all 1935 (125)I seeds implanted in the initial 28 patients in our hospital. Physical characteristics including linearity of readings for different integral time intervals, reproducibility, isotropy, and axial positional sensitivity were assessed. To calculate the source strength, the integral charge during 30 s was measured and converted to air kerma strength. The nominal activity stated by the manufacturer was compared with the measured value. RESULTS: Linearity, reproducibility, and isotropy of the well-type ionization chamber were within 0.2%. Measured source strength was on average 2.1% (range -7.6% to +7.2%), lower than the nominal value. Standard deviation of all measured seeds was 2.0%. The maximum difference between the measured and the manufacturer's nominal source strength in each patient was -3.7%. The standard deviation averaged 1.6%. CONCLUSION: The nominal source strength of the (125)I seeds agreed well with the measured value. Our study can be helpful as guidance for individual (125)I seed source strength measurement.

Brachytherapy↗

PubMed2004

Measurement characteristics of activity-related psychosocial measures in 8- to 10-year-old African-American girls in the Girls Health Enrichment Multisite Study (GEMS).

BACKGROUND: This paper presents reliability and validity analyses of physical activity-related psychosocial questionnaires completed by 8- to 10-year-old African-American girls at baseline and follow-up assessments of pilot intervention studies in the Girls health Enrichment Multi-site Study (GEMS). METHODS: Two hundred ten girls participated in the GEMS 12-week pilot studies and had their height and weight measured, wore an accelerometer for 3 days and completed a measure of their usual physical activity (PA) at baseline and after the 12-week intervention. Subgroups of girls also completed physical activity-related psychosocial measures at these two time points including: (a) self-concept; (b) self-efficacy; (c) outcome expectancies; and d) preferences. Principal components analysis was conducted on the psychosocial measures obtained at baseline. Cronbach's alpha and test-retest reliability were computed. Convergent validity was assessed by correlating the baseline psychosocial measures with baseline physical activity measures and body mass index (BMI). RESULTS: The following sub-scales were derived: Activity Preference, Positive Expectancies and Negative Expectancies for physical activity. Physical Performance Self-Concept and Self-Efficacy for physical activity were kept as single dimensional scales. Sub-scales, derived from principal components analyses, were Activity Preference, Positive Expectancies, and Negative Expectancies for physical activity. Internal consistency estimates for the various scales were substantial to excellent (0.67-0.85), while test-retest reliability estimates were fair to moderate (0.22-0.56). Correlations between the PA psychosocial sub-scales and measured levels of activity measures showed evidence of convergent validity for the Activity Preference sub-scale, although social desirability may have influenced the significant associations observed. CONCLUSIONS: The Activity Preference was a fairly reliable and valid measure. Further studies are needed to examine the utility of activity-related psychosocial measures in interventions to increase physical activity among preadolescent African-American girls.

Black or African American↗

PubMed2003

Tumour size measurement in an oncology clinical trial: comparison between off-site and on-site measurements.

AIM: To evaluate the degree of variability between lesion measurements obtained by a single observer compared with multiple observers, and in selected cases evaluate which of the two measurements more accurately represented the lesion size. MATERIALS AND METHODS: In this study we compared the performance of a single off-site observer to multiple on-site observers during measurement of 300 abdominal and thoracic lesions. Lesion measurements that were larger than 1cm(2), differed by more than 50%, but by less than 100%, were compared by a single adjudicator, who was blinded to the measurement source (n=46). RESULTS: Measurements of the 300 lesions differed by an average of 109% (SD 251%). Of 266 lesions larger than 1cm(2), results of the single observer compared with multiple observers differed by more than 10% for 249 lesions, more than 30% for 169 lesions, more than 50% for 126 lesions, and more than 100% for 66 lesions. Forty-six lesions were compared by the adjudicator. The adjudicator selected the measurement of the single observer for 37 lesions (80.4%), and the measurement determined by one of the multiple observers for nine lesions (19.6%; p=0.00002). CONCLUSION: Measurement of lesion size by a single observer compared with multiple observers reveals a high degree of variability. An adjudicator selected the measurement of the single observer more frequently than that of multiple observers, with statistical significance. These findings suggest that studies designed to quantify imaging features should limit the number of observers.

Abdominal Neoplasms↗

PubMed1996

Seminal fluid antisperm antibodies measured by direct flow cytometry do not correlate with those measured by indirect flow cytometry, the indirect immunobead test, and the indirect mixed antiglobulin reaction.

OBJECTIVE: To compare the direct flow cytometric (FCM) measurement of sperm-bound antibodies with the indirect FCM measurement of unbound antisperm antibodies in seminal plasma of the same ejaculates. To compare the FCM measurements with the indirect mixed antiglobulin reaction (MAR) and the indirect immunobead test (IBT) performed on the same seminal plasmas. SETTING: University hospital-based infertility service. PATIENTS: Eleven infertile men with a positive immunoglobulin (Ig) G direct MAR test and antibody positivity on the direct FCM measurements. Four control patients with a negative IgG-direct MAR test. MAIN OUTCOME MEASURES: The proportion of spermatozoa positive for IgG and IgA antibodies as measured by various tests. RESULTS: The direct and indirect FCM measurements for sperm-bound antibodies from seminal plasma did not correlate with each other. In general, IgG antibodies were not detectable by indirect FCM whereas IgA were detected in lower proportions than by direct FCM measurements. Weak correlation was observed between the indirect FCM, indirect MAR, and indirect IBT measurements. CONCLUSION: Nearly all of the IgG and some of the IgA antisperm antibodies in seminal fluid bind to spermatozoa. Thus, indirect tests to measure antisperm antibodies from seminal plasma are likely to miss the presence of antisperm IgG antibodies while detecting some cases of IgA antibodies.

Flow Cytometry↗

PubMed1997

Measurement of very low stable isotope enrichments by gas chromatography/mass spectrometry: application to measurement of muscle protein synthesis.

Measurement of muscle protein synthesis using stable isotopically labeled tracers usually requires isotope ratio mass spectrometry (IRMS) because of the need to measure very low enrichments of stable isotopically labeled tracers (tracer to tracee ratio [TTR], 0.005% to 0.10%). This approach is laborious, requiring purification of the metabolite of interest and combustion to a gas for IRMS analysis, and is best suited for use with 13C tracers. We have developed an approach whereby low enrichments can be conveniently measured by a conventional gas chromatography/mass spectrometry (GC/MS) instrument. The approach includes three critical elements: (1) use of a highly substituted tracer containing three or more labeled atoms, to measure enrichment above a very low natural abundance of highly substituted isotopomers; (2) use of a highly substituted natural abundance isotopomer as a base ion for comparison rather than the most abundant m + 0 isotopomer, to reduce the dynamic range of the isotopomer ratio measurement; and (3) a sensitive mass spectrometric analysis that measures the natural abundance of the isotopomer used as a tracer with a high signal to noise ratio (> 100:1). This approach was used to measure the rate of synthesis of muscle protein following a primed continuous infusion of L-[13C6]-phenylalanine (PHE) in eight fasted dogs and L-[2H3]-leucine in five fasted human subjects. Values for [13C6]-PHE enrichment by GC/MS rates were virtually identical to those obtained by a conventional approach using high-performance liquid chromatography (HPLC) to isolate PHE, combustion to CO2, and measurement of 13CO2 enrichment by IRMS (IRMS enrichment = 0.9988 x GC/MS enrichment, R2 = .891), resulting in identical values for muscle fractional synthesis rates ([FSRs] mean +/- SEM: 2.7 +/- 0.2 and 2.5 +/- 0.2%/d for GC/MS and IRMS, respectively). Human muscle synthesis rates measured by GC/MS analysis of [2H3]-leucine enrichment (1.90 +/- 0.17%/d) were similar to published values based on IRMS analysis using a 1- 13C-leucine tracer. We conclude that compared with the IRMS approach, the GC/MS approach offers faster throughput, has a lower sample requirement, and is suitable for a wider variety of tracers such as 2H. The principles outlined here should be applicable to the measurement of low enrichments by GC/MS in a wide variety of stable isotope tracer applications.

Adult↗

PubMed1997

[Investigation methods in clinical cardiology. IV. Clinical measurements in cardiology: validity and errors of measurements].

Measurements represent an essential part of clinical activity. Very often, however, relevant disagreement in clinical measurements becomes apparent. The sources of this variability are the subjects (patients) that are measured, the measurement instrument itself, and the observer. The assessment of the quality of measurement usually relies on the evaluation of its reproducibility and its validity. The reproducibility is basically measured as the inter-observer concordance, the intra-observer concordance, and the test-retest concordance. The specific parameter used to its quantification (intra-class correlation coefficient, kappa index, graphic methods, etc.) depend on the kind of variable to be measured. The validity of the measurement is the degree to which the measurement is really measuring what we think it should. If an acceptable standard is available, then so called criterion validity is usually assessed. Otherwise the validity should be assessed by other ways that use subjective criteria (content validity and face validity) or empirical criteria (construct validity).

Cardiology↗

PubMed1998

Methods of measuring morphological parameters in dental radiographs. Comparison between image analysis and manual measurements.

Measurements of age-related changes in dental tissues are often used when estimating the age of an individual. With the new technology now available, the methods of measurement might be standardized and reproducible. The purpose of the present study was to compare the reliability of manual and computer-assisted measurements of morphological parameters in dental radiographs. Manual measurements were made conventionally using a pair of vernier callipers and a stereomicroscope with a measuring eyepiece. An image analysis software program was employed for the computer assisted measurements. Lengths and widths of tooth and pulp were measured both manually and with computer assistance on periapical radiographs from 40 patients, six teeth in each patient. Statistical analyses showed no significant intra- or inter-observer differences for the manual measurements. Statistically significant intra- and inter-observer differences were, however, found between the manual and computer-assisted measurements. The results implied that, despite advanced technology, conventional methods may be better suited for measuring linear morphological parameters in dental tissue.

Adult↗

PubMed1989

[Measuring the optic papilla with planimetry and the optic nerve head analyzer in glaucoma and suspected glaucoma. I. Comparison of the 2 measuring methods].

Two-dimensional planimetric measurement of the neuroretinal rim using the method described by Betz has proved to be one of the most objective parameters in evaluating the optic nerve head. Using a three-dimensional stereoscopic measuring procedure (ONHA) described by Cornsweet, the volume of the papillary excavation can be quantified. The two methods were compared in a study involving 67 eyes with confirmed and suspected glaucoma. In agreement with published data, the correlation between the two measuring procedures was good as regards the disk surface (r2 = 0.73), the surface of the excavation (r2 = 0.90), and the cup/disk ratio (r2 = 0.63), although the last-mentioned parameter is calculated differently. While the disk surface as measured by planimetry was significantly greater than with ONHA, the cup surface measurements were almost exactly the same. In contrast to the results of other authors, the measurements of the neuroretinal rim surface correlated poorly (r2 = 0.09). The difference between the two methods in measuring the rim surfaces depends to a great extent on their absolute size and on the cup surface. The different procedures for defining the boundary of the excavation (in planimetry horizontal boundary definition, with the ONHA 150 micrometers below the retinal surface) are considered responsible for this. Advantages and drawbacks of these two clinical measuring methods are discussed. Once the currently excessive variability in the measurements has been reduced, measurement of the excavation volume could prove to be an important parameter for assessing the development of the optic nerve head in confirmed or suspected glaucoma cases.

Adolescent↗

PubMed2002

Measurement error associated with spinal mobility measures in children with and without low-back pain.

AIM: Evidence of the reliability of measurements in children is scarce, particularly in children with low-back pain. The aim of this investigation was to evaluate the measurement error associated with repeated measures of spinal mobility measures in children with and without low-back pain by establishing 95% limits of agreement. METHODS: A repeated measures study was performed involving 119 children aged 11-16 y. Of this sample 30 subjects reported recurrent low-back pain and were classified as symptomatic, the remaining 89 subjects were asymptomatic. Standardized measures were taken, including the sit-and-reach test, hip range of motion (Leighton flexometer), lumbar flexibility (modified Schöber test) and lateral flexion of the spine. The same experimenter performed all testing, with 1 wk between the repeated measures. RESULTS: Correlation coefficients suggested that all measures exhibited good reliability in both the symptomatic (r = 0.80-0.95) and asymptomatic groups (r = 0.88-0.99). In contrast, the limits of agreement showed that all measures exhibited random error. The magnitude of random error was typically greater in the symptomatic subjects, suggesting that low-back pain may influence the reliability of typical measures used in this population. CONCLUSION: The magnitude of error must be interpreted in relation to analytical goals and the expected magnitude of change. In the authors' opinion the error presented appears acceptable for the serial monitoring of patients, although this will depend on the differences in mobility typically found.

Adolescent↗