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The Bone & Joint Journal
Vol. 95-B, Issue 3 | Pages 396 - 400
1 Mar 2013
Rhee SH Kim J Lee YH Gong HS Lee HJ Baek GH

The purpose of this study was to evaluate the risk of late displacement after the treatment of distal radial fractures with a locking volar plate, and to investigate the clinical and radiological factors that might correlate with re-displacement. From March 2007 to October 2009, 120 of an original cohort of 132 female patients with unstable fractures of the distal radius were treated with a volar locking plate, and were studied over a follow-up period of six months. In the immediate post-operative and final follow-up radiographs, late displacement was evaluated as judged by ulnar variance, radial inclination, and dorsal angulation. We also analysed the correlation of a variety of clinical and radiological factors with re-displacement. Ulnar variance was significantly overcorrected (p < 0.001) while radial inclination and dorsal angulation were undercorrected when compared statistically (p <  0.001) with the unaffected side in the immediate post-operative stage. During follow-up, radial shortening and dorsal angulation progressed statistically, but none had a value beyond the acceptable range. Bone mineral density measured at the proximal femur and the position of the screws in the subchondral region, correlated with slight progressive radial shortening, which was not clinically relevant.

Volar locking plating of distal radial fractures is a reliable form of treatment without substantial late displacement.

Cite this article: Bone Joint J 2013;95-B:396–400.


The Bone & Joint Journal
Vol. 95-B, Issue 7 | Pages 993 - 1000
1 Jul 2013
Lee SC Shim JS Seo SW Lim KS Ko KR

We compared the accuracy of the growth remaining method of assessing leg-length discrepancy (LLD) with the straight-line graph method, the multiplier method and their variants. We retrospectively reviewed the records of 44 patients treated by percutaneous epiphysiodesis for LLD. All were followed up until maturity. We used the modified Green–Anderson growth-remaining method (Method 1) to plan the timing of epiphysiodesis. Then we presumed that the other four methods described below were used pre-operatively for calculating the timing of epiphysiodesis. We then assumed that these four methods were used pre-operatively. Method 2 was the original Green–Anderson growth-remaining method; Method 3, Paley’s multiplier method using bone age; Method 4, Paley’s multiplier method using chronological age; and Method 5, Moseley’s straight-line graph method. We compared ‘Expected LLD at maturity with surgery’ with ‘Final LLD at maturity with surgery’ for each method. Statistical analysis revealed that ‘Expected LLD at maturity with surgery’ was significantly different from ‘Final LLD at maturity with surgery’. Method 2 was the most accurate. There was a significant correlation between ‘Expected LLD at maturity with surgery’ and ‘Final LLD at maturity with surgery’, the greatest correlation being with Method 2. Generally all the methods generated an overcorrected value. No method generates the precise ‘Expected LLD at maturity with surgery’. It is essential that an analysis of the pattern of growth is taken into account when predicting final LLD. As many additional data as possible are required.

Cite this article: Bone Joint J 2013;95-B:993–1000.


The Bone & Joint Journal
Vol. 95-B, Issue 9 | Pages 1255 - 1262
1 Sep 2013
Clement ND Beauchamp NJF Duckworth AD McQueen MM Court-Brown CM

We describe the outcome of tibial diaphyseal fractures in the elderly (≥ 65 years of age). We prospectively followed 233 fractures in 225 elderly patients over a minimum ten-year period. Demographic and descriptive data were acquired from a prospective trauma database. Mortality status was obtained from the General Register Office database for Scotland. Diaphyseal fractures of the tibia in the elderly occurred predominantly in women (73%) and after a fall (61%). During the study period the incidence of these fractures decreased, nearly halving in number. The 120-day and one-year unadjusted mortality rates were 17% and 27%, respectively, and were significantly greater in patients with an open fracture (p < 0.001). The overall standardised mortality ratio (SMR) was significantly increased (SMR 4.4, p < 0.001) relative to the population at risk, and was greatest for elderly women (SMR 8.1, p < 0.001). These frailer patients had more severe injuries, with an increased rate of open fractures (30%), and suffered a greater rate of nonunion (10%).

Tibial diaphyseal fractures in the elderly are most common in women after a fall, are more likely to be open than in the rest of the population, and are associated with a high incidence of nonunion and mortality.

Cite this article: Bone Joint J 2013;95-B:1255–62.


The Bone & Joint Journal
Vol. 97-B, Issue 5 | Pages 716 - 720
1 May 2015
Orak MM Onay T Gümüştaş SA Gürsoy T Muratlí HH

The aim of this prospective study was to investigate prematurity as a risk factor for developmental dysplasia of the hip (DDH). The hips of 221 infants (88 female, 133 male, mean age 31.11 weeks; standard deviation (sd) 2.51) who were born in the 34th week of gestation or earlier, and those of 246 infants (118 female, 128 male, mean age 40.22 weeks; sd 0.36) who were born in the 40th week of gestation, none of whom had risk factors for DDH, were compared using physical examination and ultrasound according to the technique of Graf, within one week, after the correction of gestational age to the 40th week after birth or one week since birth, respectively. Both hips of all infants were included in the study. Ortolani’s and Barlow’s tests and restricted abduction were accepted as positive findings on examination. There was a statistically significant difference between pre- and full-term infants, according to the incidence of mature and immature hips (p < 0.001). The difference in the proportion of infants with an α angle < 60° between the two groups was statistically significant (p < 0.001). The incidence of pathological dysplasia (α angle < 50 º) was not significantly different in the two groups (p = 1.000). The Barlow sign was present in two (0.5%) pre-term infants and in 14 (2.8%) full-term infants.

These results suggests that prematurity is not a predisposing factor for DDH.

Cite this article: Bone Joint J 2015; 97-B:716–20


Bone & Joint Research
Vol. 3, Issue 11 | Pages 317 - 320
1 Nov 2014
Basso T Klaksvik J Foss OA

Objective

In ex vivo hip fracture studies femoral pairs are split to create two comparable test groups. When more than two groups are required, or if paired femurs cannot be obtained, group allocation according to bone mineral density (BMD) is sometimes performed. In this statistical experiment we explore how this affects experimental results and sample size considerations.

Methods

In a hip fracture experiment, nine pairs of human cadaver femurs were tested in a paired study design. The femurs were then re-matched according to BMD, creating two new test groups. Intra-pair variance and paired correlations in fixation stability were calculated. A hypothetical power analysis was then performed to explore the required sample size for the two types of group allocation.


The Bone & Joint Journal
Vol. 97-B, Issue 3 | Pages 346 - 352
1 Mar 2015
Chadwick C Whitehouse SL Saxby TS

Flexor digitorum longus transfer and medial displacement calcaneal osteotomy is a well-recognised form of treatment for stage II posterior tibial tendon dysfunction. Although excellent short- and medium-term results have been reported, the long-term outcome is unknown. We reviewed the clinical outcome of 31 patients with a symptomatic flexible flat-foot deformity who underwent this procedure between 1994 and 1996. There were 21 women and ten men with a mean age of 54.3 years (42 to 70). The mean follow-up was 15.2 years (11.4 to 16.5). All scores improved significantly (p < 0.001). The mean American Orthopedic Foot and Ankle Society (AOFAS) score improved from 48.4 pre-operatively to 90.3 (54 to 100) at the final follow-up. The mean pain component improved from 12.3 to 35.2 (20 to 40). The mean function score improved from 35.2 to 45.6 (30 to 50). The mean visual analogue score for pain improved from 7.3 to 1.3 (0 to 6). The mean Short Form-36 physical component score was 40.6 (sd 8.9), and this showed a significant correlation with the mean AOFAS score (r = 0.68, p = 0.005). A total of 27 patients (87%) were pain free and functioning well at the final follow-up. We believe that flexor digitorum longus transfer and calcaneal osteotomy provides long-term pain relief and satisfactory function in the treatment of stage II posterior tibial tendon dysfunction.

Cite this article: Bone Joint J 2015;97-B:346–52.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 7 | Pages 868 - 873
1 Jul 2007
Ng CY Ballantyne JA Brenkel IJ

We have evaluated the quality of life and functional outcome after unilateral primary total hip replacement (THR). Between 5 January 1998 and 31 July 2000, we recruited a consecutive series of 627 patients undergoing this procedure and investigated them prospectively. Each was assessed before operation and reviewed after six months, 18 months, three years and five years. The Short Form-36 Health Survey (SF-36) and Harris Hip scores were evaluated at each appointment.

All dimensions of the SF-36 except for mental health and general health perception, improved significantly after operation and this was maintained throughout the follow-up. The greatest improvement was seen at the six-month assessment. On average, women reported lower SF-36 scores pre-operatively, but the gender difference did not continue post-operatively. The Harris Hip scores improved significantly after operation, reaching a plateau after 18 months. The improved quality of life was sustained five years after THR.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 9 | Pages 1187 - 1192
1 Sep 2012
Rakhra KS Lattanzio P Cárdenas-Blanco A Cameron IG Beaulé PE

Advanced MRI cartilage imaging such as T1-rho (T1ρ) for the diagnosis of early cartilage degradation prior to morpholgic radiological changes may provide prognostic information in the management of joint disease. This study aimed first to determine the normal T1ρ profile of cartilage within the hip, and secondly to identify any differences in T1ρ profile between the normal and symptomatic femoroacetabular impingement (FAI) hip. Ten patients with cam-type FAI (seven male and three female, mean age 35.9 years (28 to 48)) and ten control patients (four male and six female, mean age 30.6 years (22 to 35)) underwent 1.5T T1ρ MRI of a single hip. Mean T1ρ relaxation times for full thickness and each of the three equal cartilage thickness layers were calculated and compared between the groups. The mean T1ρ relaxation times for full cartilage thickness of control and FAI hips were similar (37.17 ms (sd 9.95) and 36.71 ms (sd 6.72), respectively). The control group demonstrated a T1ρ value trend, increasing from deep to superficial cartilage layers, with the middle third having significantly greater T1ρ relaxation values than the deepest third (p = 0.008). The FAI group demonstrated loss of this trend. The deepest third in the FAI group demonstrated greater T1ρ relaxation values than controls (p = 0.028).

These results suggest that 1.5T T1ρ MRI can detect acetabular hyaline cartilage changes in patients with FAI.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 9 | Pages 1238 - 1244
1 Sep 2010
Nicoll D Rowley DI

This study used CT analysis to determine the rotational alignment of 39 painful and 26 painless fixed-bearing total knee replacements (TKRs) from a cohort of 740 NexGen Legacy posterior-stabilised and cruciate-retaining prostheses implanted between May 1996 and August 2003.

The mean rotation of the tibial component was 4.3° of internal rotation (25.4° internal to 13.9° external rotation) in the painful group and 2.2° of external rotation (8.5° internal to 18.2° external rotation) in the painfree group (p = 0.024). In the painful group 17 tibial components were internally rotated more than 9° compared with none in the painfree group (p < 0.001). Additionally, six femoral components in the painful group were internally rotated more than 6° compared with none in the painfree group (p = 0.017). External rotational errors were not found to be associated with pain.

Overall, 22 (56.4%) of the painful TKRs had internal rotational errors involving the femoral, the tibial or both components. It is estimated that at least 4.6% of all our TKRs have been implanted with significant internal rotational errors.


The Bone & Joint Journal
Vol. 95-B, Issue 1 | Pages 52 - 58
1 Jan 2013
Clement ND Jenkins PJ DM Nie YX Patton JT Breusch SJ Howie CR Biant LC

We assessed the effect of social deprivation upon the Oxford knee score (OKS), the Short-Form 12 (SF-12) and patient satisfaction after total knee replacement (TKR). An analysis of 966 patients undergoing primary TKR for symptomatic osteoarthritis (OA) was performed. Social deprivation was assessed using the Scottish Index of Multiple Deprivation. Those patients that were most deprived underwent surgery at an earlier age (p = 0.018), were more likely to be female (p = 0.046), to endure more comorbidities (p = 0.04) and to suffer worse pain and function according to the OKS (p < 0.001). In addition, deprivation was also associated with poor mental health (p = 0.002), which was assessed using the mental component (MCS) of the SF-12 score. Multivariable analysis was used to identify independent predictors of outcome at one year. Pre-operative OKS, SF-12 MCS, back pain, and four or more comorbidities were independent predictors of improvement in the OKS (all p < 0.001). Pre-operative OKS and improvement in the OKS were independent predictors of dissatisfaction (p = 0.003 and p < 0.001, respectively). Although improvement in the OKS and dissatisfaction after TKR were not significantly associated with social deprivation per se, factors more prevalent within the most deprived groups significantly diminished their improvement in OKS and increased their rate of dissatisfaction following TKR.

Cite this article: Bone Joint J 2013;95-B:52–8.


The Bone & Joint Journal
Vol. 97-B, Issue 4 | Pages 503 - 509
1 Apr 2015
Maempel JF Clement ND Brenkel IJ Walmsley PJ

This study demonstrates a significant correlation between the American Knee Society (AKS) Clinical Rating System and the Oxford Knee Score (OKS) and provides a validated prediction tool to estimate score conversion.

A total of 1022 patients were prospectively clinically assessed five years after TKR and completed AKS assessments and an OKS questionnaire. Multivariate regression analysis demonstrated significant correlations between OKS and the AKS knee and function scores but a stronger correlation (r = 0.68, p < 0.001) when using the sum of the AKS knee and function scores. Addition of body mass index and age (other statistically significant predictors of OKS) to the algorithm did not significantly increase the predictive value.

The simple regression model was used to predict the OKS in a group of 236 patients who were clinically assessed nine to ten years after TKR using the AKS system. The predicted OKS was compared with actual OKS in the second group. Intra-class correlation demonstrated excellent reliability (r = 0.81, 95% confidence intervals 0.75 to 0.85) for the combined knee and function score when used to predict OKS.

Our findings will facilitate comparison of outcome data from studies and registries using either the OKS or the AKS scores and may also be of value for those undertaking meta-analyses and systematic reviews.

Cite this article: Bone Joint J 2015;97-B:503–9.


The Bone & Joint Journal
Vol. 97-B, Issue 2 | Pages 270 - 276
1 Feb 2015
Koch A Jozwiak M Idzior M Molinska-Glura M Szulc A

We investigated the incidence and risk factors for the development of avascular necrosis (AVN) of the femoral head in the course of treatment of children with cerebral palsy (CP) and dislocation of the hip. All underwent open reduction, proximal femoral and Dega pelvic osteotomy. The inclusion criteria were: a predominantly spastic form of CP, dislocation of the hip (migration percentage, MP > 80%), Gross Motor Function Classification System, (GMFCS) grade IV to V, a primary surgical procedure and follow-up of > one year.

There were 81 consecutive children (40 girls and 41 boys) in the study. Their mean age was nine years (3.5 to 13.8) and mean follow-up was 5.5 years (1.6 to 15.1). Radiological evaluation included measurement of the MP, the acetabular index (AI), the epiphyseal shaft angle (ESA) and the pelvic femoral angle (PFA). The presence and grade of AVN were assessed radiologically according to the Kruczynski classification.

Signs of AVN (grades I to V) were seen in 79 hips (68.7%). A total of 23 hips (18%) were classified between grades III and V.

Although open reduction of the hip combined with femoral and Dega osteotomy is an effective form of treatment for children with CP and dislocation of the hip, there were signs of avascular necrosis in about two-thirds of the children. There was a strong correlation between post-operative pain and the severity of the grade of AVN.

Cite this article: Bone Joint J 2015;97-B:270–6.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 1 | Pages 32 - 36
1 Jan 2012
Nho J Lee Y Kim HJ Ha Y Suh Y Koo K

A variety of radiological methods of measuring version of the acetabular component after total hip replacement (THR) have been described. The aim of this study was to evaluate the reliability and validity of six methods (those of Lewinnek; Widmer; Hassan et al; Ackland, Bourne and Uhthoff; Liaw et al; and Woo and Morrey) that are currently in use. In 36 consecutive patients who underwent THR, version of the acetabular component was measured by three independent examiners on plain radiographs using these six methods and compared with measurements using CT scans. The intra- and interobserver reliabilities of each measurement were estimated. All measurements on both radiographs and CT scans had excellent intra- and interobserver reliability and the results from each of the six methods correlated well with the CT measurements. However, measurements made using the methods of Widmer and of Ackland, Bourne and Uhthoff were significantly different from the CT measurements (both p < 0.001), whereas measurements made using the remaining four methods were similar to the CT measurements. With regard to reliability and convergent validity, we recommend the use of the methods described by Lewinnek, Hassan et al, Liaw et al and Woo and Morrey for measurement of version of the acetabular component.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 8 | Pages 1060 - 1063
1 Aug 2007
Singh PJ Perera NS Dega R

We carried out a prospective study over a period of 12 months to measure the exposure to radiation of the hands of a dedicated foot and ankle surgeon. A thermoluminescent dosimeter ring (TLD) was used to measure the cumulative dose of radiation. Fluoroscopy was used in operations on the foot and ankle. The total screening time was 3028 s, with a mean time per procedure of 37.4 s (0.6 to 197). This correlated positively with the number of procedures performed (r = 0.92, p < 0.001), and with the dose of radiation in both the left (r = 0.85, p = 0.0005) and right TLDs (r = 0.59, p = 0.419). There was no significant difference in the dose of radiation between the two hands (t-test, p = 0.62). The total dose to the right TLD over the 12 months was 2.4 millisieverts.

This is a simple and convenient method for evaluating the exposure of a single surgeon to radiation. The radiation detected was well below the annual dose limit set by the International Commission on Radiological Protection.


The Journal of Bone & Joint Surgery British Volume
Vol. 93-B, Issue 5 | Pages 629 - 633
1 May 2011
Hirschmann MT Konala P Amsler F Iranpour F Friederich NF Cobb JP

We studied the intra- and interobserver reliability of measurements of the position of the components after total knee replacement (TKR) using a combination of radiographs and axial two-dimensional (2D) and three-dimensional (3D) reconstructed CT images to identify which method is best for this purpose.

A total of 30 knees after primary TKR were assessed by two independent observers (an orthopaedic surgeon and a radiologist) using radiographs and CT scans. Plain radiographs were highly reliable at measuring the tibial slope, but showed wide variability for all other measurements; 2D-CT also showed wide variability. 3D-CT was highly reliable, even when measuring rotation of the femoral components, and significantly better than 2D-CT. Interobserver variability in the measurements on radiographs were good (intraclass correlation coefficient (ICC) 0.65 to 0.82), but rotational measurements on 2D-CT were poor (ICC 0.29). On 3D-CT they were near perfect (ICC 0.89 to 0.99), and significantly more reliable than 2D-CT (p < 0.001).

3D-reconstructed images are sufficiently reliable to enable reporting of the position and orientation of the components. Rotational measurements in particular should be performed on 3D-reconstructed CT images. When faced with a poorly functioning TKR with concerns over component positioning, we recommend 3D-CT as the investigation of choice.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 9 | Pages 1203 - 1208
1 Sep 2010
Brunner A Hamers AT Fitze M Herzog RF

The β-angle is a radiological tool for measuring the distance between the pathological head-neck junction and the acetabular rim with the hip in 90° of flexion in patients with femoroacetabular impingement. Initially it was measured using an open-chamber MRI. We have developed a technique to measure this angle on plain radiographs. Correlation analysis was undertaken to determine the relationship between the range of movement and the β-angle in 50 patients with femoroacetabular impingement and 50 asymptomatic control subjects. Inter- and intra-observer reliability of the β-angle was also evaluated.

Patients with femoroacetabular impingement had a significantly smaller (p < 0.001) mean β-angle (15.6°, 95% confidence interval (CI) 13.3 to 17.7) compared with the asymptomatic group (38.7°, 95% CI 36.5 to 41.0). Correlation between internal rotation and the β-angle was high in the impingement group and moderate in the asymptomatic group. The β-angle had excellent inter- and intra-observer reliability in both groups.

Our findings suggest that the measurement of the β-angle on plain radiography may represent a valid, reproducible and cost-effective alternative to open MRI in the assessment of the pathological bony anatomy in patients with cam, pincer and mixed femoroacetabular impingement.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 9 | Pages 1253 - 1258
1 Sep 2010
Scott CEH Howie CR MacDonald D Biant LC

Up to 20% of patients are not satisfied with the outcome following total knee replacement (TKR). This study investigated the pre- and post-operative predictors of dissatisfaction in a large cohort of patients undergoing TKR. We assessed 1217 consecutive patients between 2006 and 2008 both before operation and six months after, using the Short-form (SF)-12 health questionnaire and the Oxford Knee Score. Detailed information concerning comorbidity was also gathered. Satisfaction was measured at one year when 18.6% (226 of 1217) of patients were unsure or dissatisfied with their replacement and 81.4% (911 of 1217) were satisfied or very satisfied. Multivariate regression analysis was performed to identify independent predictors of dissatisfaction. Significant (p < 0.001) predictors at one year included the pre-operative SF-12 mental component score, depression and pain in other joints, the six-month SF-12 score and poorer improvement in the pain element of the Oxford Knee Score.

Patient expectations were highly correlated with satisfaction. Satisfaction following TKR is multifactorial. Managing the expectations and mental health of the patients may reduce dissatisfaction. However, the most significant predictor of dissatisfaction is a painful total knee replacement.


The Bone & Joint Journal
Vol. 95-B, Issue 9 | Pages 1192 - 1196
1 Sep 2013
Okano K Yamaguchi K Ninomiya Y Matsubayashi S Osaki M Takahashi K

Patients with acetabular dysplasia commonly undergo peri-acetabular osteotomy after skeletal maturity to reduce the risk of the late development of osteoarthritis. Several studies have suggested that deformity of the femoral head influences the long-term outcome. We radiologically examined 224 hips in 112 patients with acetabular dysplasia and early-stage osteoarthritis. There were 103 women and nine men with a mean age of 37.6 years (18 to 49). A total of 201 hips were placed in the acetabular dysplasia group and 23 in a normal group. The centre–edge angle and acetabular head index were significantly smaller (both p < 0.001), and the acetabular angle, acetabular roof angle and roundness index were significantly greater in the acetabular dysplasia group than those in the normal group (all p < 0.001). There were significant correlations between the roundness index and other parameters. Femoral head shape may be influenced by the severity of the acetabular dysplasia.

Cite this article: Bone Joint J 2013;95-B:1192–6.


The Bone & Joint Journal
Vol. 95-B, Issue 7 | Pages 877 - 880
1 Jul 2013
Lee YK Kim TY Ha YC Kang BJ Koo KH

Version of the femoral stem is an important factor influencing the risk of dislocation after total hip replacement (THR) as well as the position of the acetabular component. However, there is no radiological method of measuring stem anteversion described in the literature. We propose a radiological method to measure stem version and have assessed its reliability and validity. In 36 patients who underwent THR, a hip radiograph and CT scan were taken to measure stem anteversion. The radiograph was a modified Budin view. This is taken as a posteroanterior radiograph in the sitting position with 90° hip flexion and 90° knee flexion and 30° hip abduction. The angle between the stem-neck axis and the posterior intercondylar line was measured by three independent examiners. The intra- and interobserver reliabilities of each measurement were examined. The radiological measurements were compared with the CT measurements to evaluate their validity. The mean radiological measurement was 13.36° (sd 6.46) and the mean CT measurement was 12.35° (sd 6.39) (p = 0.096). The intra- and interobserver reliabilities were excellent for both measurements. The radiological measurements correlated well with the CT measurements (p = 0.001, r = 0.877). The modified Budin method appears reliable and valid for the measurement of femoral stem anteversion.

Cite this article: Bone Joint J 2013;95-B:877–80.


Bone & Joint Research
Vol. 3, Issue 3 | Pages 69 - 75
1 Mar 2014
Parsons N Griffin XL Achten J Costa ML

Objectives

To study the measurement properties of a joint specific patient reported outcome measure, a measure of capability and a general health-related quality of life (HRQOL) tool in a large cohort of patients with a hip fracture.

Methods

Responsiveness and associations between the Oxford Hip Score (a hip specific measure: OHS), ICEpop CAPability (a measure of capability in older people: ICECAP-O) and EuroQol EQ-5D (general health-related quality of life measure: EQ-5D) were assessed using data available from two large prospective studies. The three outcome measures were assessed concurrently at a number of fixed follow-up time-points in a consecutive sequence of patients, allowing direct assessment of change from baseline, inter-measure associations and validity using a range of statistical methods.