Clinical and radiological signs of bone healing in conservatively treated fractures in adults.

Traumatic fractures are often treated conservatively. Bone healing is a complex process and the complexities of a fracture, bone quality, treatment, and patient factors are all crucial. Routine X-rays and clinical follow-ups are a significant cost to society as well as exposing the patient to increased radiation and should only be performed if there is a risk of complications that may impact the treatment. It is difficult to assess on X-rays alone, whether there is sufficient bone healing and X-rays are therefore always recommended in conjunction with clinical examination.

Pedi-IKDC exhibits questionable measurement properties in a cohort of pediatric patients with ACL rupture.

BACKGROUND: Pedi-IKDC is commonly used to evaluate anterior cruciate ligament (ACL) deficiency in children. However, its construct validity has not been thoroughly assessed. The aim was to examine the measurement properties of the Pediatric International Knee Documentation Committee (Pedi-IKDC) by modern test theory (MTT) models, confirmatory factor analysis (CFA), and item response theory (IRT). METHODS: The cohort consisted of all children and adolescents in Denmark (n = 535, age 9-16) treated with physeal-sparing ACL reconstruction 2011-2020. Patient-reported outcome measure (PROM) data were collected before surgery and at 1 year follow-up. Structural validity of Pedi-IKDC was assessed with MTT models. Reliability was reported as McDonalds coefficient omega. Responsiveness was evaluated with standardized response means. RESULTS: Sufficient PROM data were available for 372 patients. The original unidimensional construct did not fit CFA model expectations neither before surgery (χ2 = 462.0, df = 163, p < 0.0001; RMSEA: 0.109, CFI: 0.910, TFI: 0.895) nor at follow-up. Neither did a two-factor CFA model with "Symptoms" and "Sports activities" as individual subscales (χ2 = 455.6, df = 162, p < 0.0001) nor a bifactor model (χ2 = 338.9, df = 143, p < 0.0001), although fit indices improved with the latter (RMSEA: 0.094, CFI: 0.941, TFI: 0.922). The IRT models confirmed this pattern. The scale was responsive (SRM 1.66 (95% CI: 1.46-1.88)). Coefficient omega values were 0.866 before surgery and 0.919 at follow-up. CONCLUSIONS: The Pedi-IKDC exhibited inadequate structural validity. Neither the original construct, a two-factor model, nor bifactor models fitted data well. We advise that data obtained by Pedi-IKDC are interpreted with caution.

KOOS-Child exhibits inadequate structural validity in a cohort of paediatric patients with ACL deficiency.

OBJECTIVES: Knee injury and Osteoarthritis Outcome Score (KOOS)-Child is a modification of the adult KOOS aiming to evaluate knee injury, including ACL deficiency. However, the measurement properties of KOOS-Child have not been assessed in a cohort of children with ACL deficiency. We aimed to study the structure of KOOS-Child using modern test theory models (Rasch analysis and confirmatory factor analysis (CFA)). METHODS: Data were collected prospectively in a cohort of children with ACL deficiency at three time points: before-and-after ACL surgery, and at 1-year follow-up. For each subscale, structural validity through the fit of a CFA model was evaluated for 153 respondents. Modification indices were examined to find the model of best fit, confirmed using Rasch analysis. Responsiveness was reported for each subscale. Reliability was calculated for each item. Floor and ceiling effects, and Person-item distribution were reported. RESULTS: All subscales showed inadequate fit to a unidimensional CFA model. Rasch analysis confirmed these results. Adjusting the subscales improved model fit, although this was still quite poor, except for the quality of life subscale. With one exception, all items demonstrated ceiling effects. Person-item distribution confirmed this. Due to lack of fit, reliability was not reported. All subscales were able to detect change from baseline to 1-year follow-up. CONCLUSIONS: KOOS-Child exhibits inadequate measurement properties in its current form for children with ACL deficiency. Suggestions to make the subscales fit the models better and improve accuracy of KOOS-Child are presented. However, the large ceiling effects observed may reduce sensitivity and induce type 2 errors.

Four of five frequently used orthopedic PROMs possess inadequate content validity: a COSMIN evaluation of the mHHS, HAGOS, IKDC-SKF, KOOS and KNEES-ACL.

PURPOSE: Content validity is the most important property of PROMs. The COSMIN initiative has published guidelines for evaluating the content validity of PROMs, but they have only sparsely been applied to relevant PROMs for musculoskeletal conditions. The aim of this study was to use the COSMIN Risk of Bias checklist to evaluate the content validity of five PROMs, that are highly relevant in musculoskeletal research and used by the arthroscopic surgery community: the modified Harris' Hip Score (mHHS), the Copenhagen Hip and Groin Outcome Score (HAGOS), the International Knee Documentation Committee Subjective Knee evaluation Form (IKDC-SKF), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Knee Numeric-Entity Evaluation Score ACL (KNEES-ACL). METHODS: The development articles for the five PROMs were identified through searches in PubMed and SCOPUS. A literature search was performed to identify additional studies assessing content validity of the PROMs. Additional information, necessary for the assessments, was obtained from the PROM developers after direct request. To evaluate the quality of the development studies and rate the content validity, the COSMIN Risk of Bias checklist was applied to all studies. RESULTS: All five development studies were identified. Three subsequent content validity studies were identified, all evaluating KOOS and one also IKDC. One content validity study was of inadequate quality and excluded from further analysis. The development of mHHS, IKDC-SKF, and KOOS was rated inadequate and possess insufficient content validity for their target populations. Due to the irrelevance of multiple items, KOOS was in particular inappropriate to evaluate patients with an ACL injury. The development of HAGOS was also rated inadequate, although the insufficiency aspects can be regarded as minor. KNEES-ACL possessed sufficient content validity. CONCLUSION: Out of five PROMs, only KNEES-ACL possessed sufficient content validity. Particularly, KOOS should not be used as an outcome for patients with an ACL injury. There is an urgent need for condition-specific PROMs for musculoskeletal conditions, developed with adequate methods. LEVEL OF EVIDENCE: III.

Dual-panel translation to Danish and Rasch validation of the Foot and Ankle Ability Measure (FAAM-DK).

BACKGROUND: The Foot and Ankle Ability Measure (FAAM) was developed by involvement of patients with chronic ankle instability (CAI) and has acceptable measurement properties, but is not available in Danish. METHODS: FAAM was translated and culturally adapted into Danish, and its measurement properties were assessed using Rasch analyses. RESULTS: A Danish version was produced with small adaptations, and content relevance was confirmed by Danish patients. The 21-item ADL domain showed misfit to the Rasch model, but after removing six items, the resulting 15-item scale displayed adequate fit. The Sports domain also exhibited misfit, but after removing one item and adjusting due to differential item functioning related to age for another item, a 7-item scale showed good fit. This resulted in a 22-item 2-dimensional Danish version of FAAM. CONCLUSION: The 22-item Danish FAAM exhibits robust measurement properties for patients with various conditions of the lower leg, ankle, and foot, including CAI.

Patient reported outcome measures for ankle instability. An analysis of 17 existing questionnaires.

BACKGROUND: Patient reported outcome measures (PROMs) are essential for evaluating treatment of ankle instability (AI). The aim was to assess the content validity and the measurement properties of all relevant PROMs for AI. METHODS: Relevant PROMs were identified from PubMed and SCOPUS. The development and validation quality of the PROMs was assessed according to established scientific standards. RESULTS: Seventeen PROMs and 56 validation studies were analyzed. Content validity, which ensures the PROM measures what is relevant, is obtained by involving target patients in the development process. Only three PROMs identified had some degree of patient involvement (Cumberland Ankle Instability Tool (CAIT), Lower Extremity Function Scale (LEFS), and the Foot and Ankle Ability Measure (FAAM)). Of these, only FAAM was somewhat rigorously validated using modern psychometric validation methods, and exhibited superior measurement properties (construct validity). CONCLUSION: No existing PROM is completely adequate to evaluate AI. However, FAAM is the best choice.

Responsiveness, minimal important difference, minimal relevant difference, and optimal number of patients for a study.

Several terms are used to describe changes in PROM scores in relation to treatments. Whether the change is small, large, or relevant is defined in different ways, yet these change scores are used to recommend or oppose treatments. They are also used to calculate the necessary number of patients for a study. This article offers a theoretical explanation behind the terms responsiveness, minimal important difference (MID), minimal important change (MIC), minimal relevant difference (MIREDIF), and threshold of clinical importance. It also gives instructions on how these and the optimal number of patients for a study are calculated. Responses to two domains of the Knee Injury and Osteoarthritis Outcome Score (KOOS), before and 1 year after reconstruction of the anterior cruciate ligament of 164 patients, are used to illustrate the calculations. This paper presents the most common methods used to calculate and interpret MID. Results vary substantially across domains, patient location on the scale, and health conditions. The optimal number of patients depends on the minimal relevant difference (MIREDIF), the standard error of the measure (SEM), the desired statistical power for the measurement, and the responsiveness of the measurement instrument (the PROM). There is often uncertainty surrounding the calculation and interpretation of responsiveness, MID, and MIREDIF, as these concepts are complex. When MID is used to evaluate research results, authors should specify how the MID was calculated, and its relevance for the study population. These measures should only be used after thorough consideration to justify healthcare decisions.

How to translate and locally adapt a PROM. Assessment of cross-cultural differential item functioning.

Translating patient-reported outcome measures (PROMs) can alter the meaning of items and undermine the PROM's psychometric properties (quantified as cross-cultural differential item functioning [DIF]). The aim of this paper was to present the theoretical background for PROM translation, adaptation, and cross-cultural validation, and assess how PROMs used in sports medicine research have been translated and adapted. We also assessed DIF for the Knee Injury and Osteoarthritis Outcome Score (KOOS) across Danish, Norwegian, and Swedish versions. We conducted a search in PubMed and Scopus to identify the method of translation, adaptation, and validation of PROMs relevant to musculoskeletal research. Additionally, 150 preoperative KOOS questionnaires were obtained from the Scandinavian knee ligament reconstruction registries, and cross-cultural DIF was evaluated using confirmatory factor analysis and Rasch analysis. There were 392 studies identified, describing the translation of 61 PROMs. Ninety-four percent were performed with forward-backward technique. Forty-nine percent used cognitive interviews to ensure appropriate wording, understandability, and adaptation to the target culture. Only two percent were validated according to modern test theory. No study assessed cross-cultural DIF. One KOOS subscale showed no cross-cultural DIF, two had DIF with respect to some (but not all) items, and thus conversion tables could be constructed, and two KOOS subscales could not be pooled. Most PROM translations are of undocumented quality, despite the common conclusion that they are valid and reliable. Scores from three of five KOOS subscales can be pooled across the Danish, Norwegian, and Swedish versions, but two of these must be adjusted for DIF.

How to develop a condition-specific PROM.

Developing new patient-reported outcome measures (PROMs) for application in clinical studies can be necessary if an adequate PROM does not exist. For adequate measurement, it is essential that the PROM has face validity (ie, is perceived to be relevant by clinicians and researchers) and has high content validity (ie, content relevance and content coverage for the targeted patient group). The steps needed to create PROMs that possess face and content validity for a specific condition are described in this paper. Face validity is achieved by item identification and generation through literature review. Content validity is confirmed through repetitive cognitive interviews of patients from the targeted patient group in order to generate a consensus-based pilot-version of the new PROM. This qualitative process ensures that items are appropriately worded, understandable, and minimizes doubts about how items should be answered. A practical example of this process is presented, which shows the development of the Knee Numeric-Entity Evaluation Score (KNEES-ACL), a condition-specific PROM for patients with deficiency of the anterior cruciate ligament (ACL).

What is a PROM and why do we need it?

The purpose of this article was to introduce the reader to the nature of patient-reported outcome measures (PROMs) and pitfalls in their use. PROMs collect subjective information directly from the patient regarding specific or general conditions and add to clinical and functional outcomes, and turn unmeasurable subjective qualities into quantitative measures. PROMs are questionnaires consisting of items: questions or statements with predefined response options. The items in an adequate PROM have been developed by involvement of patients with the condition in focus, and the PROM has been validated for these patients using suitable statistical methods. An adequate well-targeted PROM is more responsive than an inadequate PROM. Unfortunately, many studies use inadequate PROMs as outcomes. The methods used to generate PROMs should be described as thoroughly as those used to develop any other types of measurement instruments, and the choice of PROM should always be explained and thereby justified. If the PROM used is not adequate, the consequences for the interpretation of the results should be discussed. In many cases, an adequate PROM does not exist. If the best available PROM is chosen, there are methods to validate the adequacy of the chosen PROM, which make an interpretation of the study results possible.

Psychometric validation of PROM instruments.

The aim was to provide an overview of the different statistical methods for validation of patient-reported outcome measures, ranging from simple statistical methods available in all software packages to advanced statistical models that require specialized software. A non-technical summary of classical test theory (CTT) and modern test theory (MTT) is provided. Specifically, confirmatory factor analysis, item response theory, and Rasch analysis is outlined. One CTT and three MTT methods were used to validate the two subscales (Symptoms and Quality of Life) from the Knee Injury and Osteoarthritis Outcome Score (KOOS). For each methodology, two analyses were considered: (i) a unidimensional analysis ignoring the pre-specified dimensionality, and (ii) a two-dimensional analysis using the pre-specified dimensionality. While CTT did not adequately address central issues regarding the validity of the KOOS subscales, the three MTT methods yielded very similar results. In conclusion, MTT methods offer analysis of all relevant properties related to the validity of patient-reported outcome measures, while this is not the case for CTT. Claims about sufficient validity based on CTT methods are inadequate and should not be trusted.

Choosing the most appropriate PROM for clinical studies in sports medicine.

Choosing the most appropriate patient-reported outcome measure (PROM) for a clinical study is essential in order to achieve trustworthy results. This choice will depend on (a) the objective of the study and hence the research question; (b) the choice of a theoretical framework, such as the World Health Organization's International Classification of Functioning, Disability, and Health (ICF); (c) whether there currently is a PROM that possesses high content validity and high construct validity for the specific patient group and objective, and if not; (d) the decision on whether to use a suboptimal PROM or develop and validate a new PROM. This paper presents the steps that should be followed in order to assess the relevance of PROMs and suggests ways to enhance the choice depending on the goal of the study.

Are adequate PROMs used as outcomes in randomized controlled trials? an analysis of 54 trials.

Results by patient-reported outcome measures (PROMs) from randomized controlled trials (RCTs) in musculoskeletal research often influence healthcare strategies. We aimed to evaluate to which extent these RCTs use adequate PROMs, and how this influences the results and conclusions. We identified RCTs of sports research relevance with PROMs as primary outcomes published in 13 preselected journals between January 1, 2008, and November 1, 2019; all journals regularly publish results from musculoskeletal research. Five journals have a high impact factor (>15), and eight with lower impact factors are widely read journals. It was assessed whether the RCTs had used PROMs with high content validity and whether the most adequate PROMs were used (ie, the most well developed and well validated for the patients enrolled in the study). We registered journal impact factor, year of publication, existence of a registered protocol, and whether the study showed significant difference between interventions. A total of 54 RCTs with 56 primary outcomes comprising 26 different PROMs were identified. For 13 RCTs (24%), a protocol was not published. In only 24 of RCTs (44%), the most appropriate PROM had been used as primary outcome, independent of a registered protocol, ranking of the journal, and year of publication. In seven cases, PROMs were used to evaluate a condition that they had not been developed for. RCTs that used the most adequate PROM showed significantly more often (46%) difference in outcomes in contrast to RCTs that used inadequate PROMs (22%) (P = 0.0483). In conclusion, in the majority of RCTs, the most adequate PROM had not been used. Studies, in which the most adequate PROM had been used as outcome, were significantly more likely to show significant difference between interventions. The extent to which protocols were not available was surprisingly high. Journals should request that adequate PROMs are used in RCTs, and if this is not the case that it is discussed how it might influence the results and conclusions. Likewise, it should be requested that a protocol is published or registered.

Potential problems in the use of patient reported outcome measures (PROMs) and reporting of PROM data in sports science.

To use an inadequate patient reported outcome measure (PROM) or use a PROM in an inappropriate way potentially influences the quality of measurement. The objectives of this study were to define potential inadequate uses of PROMs in sports research studies and estimate how often they occur. A consensus group consisting of medical researchers, statisticians, and psychometricians identified and defined potentially irregular applications of PROMs. Occurrence of these in 349 consecutive articles in sports medicine in which PROMs were used as primary outcomes was reviewed. In all, 14 different potential problems were defined, and one or several occurred in 172 of the articles (49%). These were as follows: using a PROM that was developed for a different patient group (100 cases), using two or more PROMs with identical questions (94), aggregation of domain sum scores (82), combinations of subjective and objective measures (27), using a PROM to diagnose or evaluate the individual patient (7), using a PROM for a single limb (3), recall bias (3), exclusion of domains or items (3), construction of a PROM for a specific occasion (2), categorization of the scale (2), and mixing different versions of a PROM (1). Adaption of scale scores (e. g., to percentage) when results are reported (144) carries a risk of miscalculation and distorted impression of results. Data related to uncertainty about completing the PROM and the handling of missing data were not provided in the manuscripts. In conclusion, potential problems in the use and reporting of PROMs are common in sports research, and this can influence the validity of reported results.

Are PROMs used adequately in sports research? An analysis of 54 randomized controlled trials with PROMs as endpoint.

Deviations from adequate use and reporting of PROMs may be problematic and misleading. The aim of this study was to investigate the extent of such problems in randomized clinical trials (RCTs). RCTs involving sports medicine research that used PROMs as primary outcomes were identified in 13 preselected journals. The articles were reviewed for nine potential problems related to how the PROM was used and how the data had been reported. The potential problems were as follows: aggregating subscale scores; combining patient-reported scores with physical, clinical, or para-clinical measures; using a PROM to diagnose or evaluate the individual patient; using a PROM for one leg or arm; selectively excluding domains or items; constructing a PROM for the specific occasion; mixing PROM formats (ie, digital, paper, telephone, e-mail, in person); ambiguous instructions for how the PROM should be completed; and recall bias. As covariates, we registered journal impact factor, year of publication, and existence of a registered protocol. In 29 (53.7%) of 54 identified RCTs, at least one potential problem was identified, the most common being aggregation of domain scores. This was not different with a published protocol or dependent on journal rankings, except for exclusion of domains, which was most common in high-ranking journals. Aggregation of domain scores was significantly less common in recently published articles compared with older articles (P = .03). Potential problematic use of PROMs and reporting of PROM data are common in RCTs, also in high-ranking journals, but less so in more recent articles.