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PubMed2006

The five-factor model of the Positive and Negative Syndrome Scale II: a ten-fold cross-validation of a revised model.

OBJECTIVE: The lack of fit of 25 previously published five-factor models for the PANSS items, can be due to the statistics used. The purpose of this study was to use a 'new' statistical method to develop and confirm an improved five-factor model. The improved model is both complex and stable. Complex means that symptoms can have multiple factor loadings, because they have multiple causes, not because they are ill defined. Stable means that the complex structure is found repeatedly in validations. METHODS: A ten-fold cross-validation (10 CV) was applied on a large data set (N = 5769) to achieve an improved factor model for the PANSS items. The advantages of 10 CV are minimal effect of sample characteristics and the ability to investigate the stability of items loading on multiple factors. RESULTS: The results show that twenty-five items contributed to the same factor all ten validations with one item showing a consistent loading on two factors. Three items were contributing to the same factor nine out of ten validations, and two items were contributing to the same factor six to eight times. The resulting five-factor model covers all thirty items of the PANSS, subdivided in the factors: positive symptoms, negative symptoms, disorganization, excitement, and emotional distress. The five-factor model has a satisfactory goodness-of-fit (Comparative Fit Index = .905; Root Mean Square Error of Approximation = .052). CONCLUSIONS: The five-factor model developed in this study is an improvement above previously published models as it represents a complex factor model and is more stable.

Affect↗
PubMed2005

OAKHQOL: a new instrument to measure quality of life in knee and hip osteoarthritis.

OBJECTIVE: To develop a questionnaire with which to measure quality of life (QoL) in patients with knee and hip osteoarthritis (OA). STUDY DESIGN AND SETTING: Thirty-two caregivers and 96 OA patients were interviewed individually (using cognitive and face-to-face techniques) and in focus groups. A group of experts working independently at first and then consensually used the interview transcripts to generate a 46-item questionnaire. RESULTS: Analysis of questionnaires completed by 263 patients with hip or knee OA resulted in the exclusion of three items (two because of low reliability and one because of a low response rate). Principal component analysis revealed four factors: physical activity, mental health, social functioning, and social support. A pain dimension was individualized. Preliminary testing showed the reliability of the five dimensions to be satisfactory (intraclass correlation coefficients: 0.70-0.85), construct validity was adequate when correlated with the SF36 (Spearman correlation coefficients: 0.43-0.75), and discrimination was satisfactory. The osteoarthritis knee and hip quality of life questionnaire (OAKHQOL) consists of 43 items in five dimensions and three independent items. CONCLUSION: The OAKHQOL is the first specific knee and hip OA quality of life instrument. Its development followed an a priori structured strategy to ensure content validity. It meets psychometric requirements for validity and reliability.

Activities of Daily Living↗
PubMed2006

Analytic complexities associated with group therapy in substance abuse treatment research: problems, recommendations, and future directions.

In community-based alcoholism and drug abuse treatment programs, the vast majority of interventions are delivered in a group therapy context. In turn, treatment providers and funding agencies have called for more research on interventions delivered in groups in an effort to make the emerging empirical literature on the treatment of substance abuse more ecologically valid. Unfortunately, the complexity of data structures derived from therapy groups (because of member interdependence and changing membership over time) and the present lack of statistically valid and generally accepted approaches to analyzing these data have had a significant stifling effect on group therapy research. This article (a) describes the analytic challenges inherent in data generated from therapy groups, (b) outlines common (but flawed) analytic and design approaches investigators often use to address these issues (e.g., ignoring group-level nesting, treating data from therapy groups with changing membership as fully hierarchical), and (c) provides recommendations for handling data from therapy groups using presently available methods. In addition, promising data-analytic frameworks that may eventually serve as foundations for the development of more appropriate analytic methods for data from group therapy research (i.e., nonhierarchical data modeling, pattern-mixture approaches) are also briefly described. Although there are other substantial obstacles that impede rigorous research on therapy groups (e.g., evaluation and measurement of group process, limited control over treatment delivery ingredients), addressing data-analytic problems is critical for improving the accuracy of statistical inferences made from research on ecologically valid group-based substance abuse interventions.

Humans↗
PubMedDate not supplied

Rethinking the use of the Hogan Empathy Scale: a critical psychometric analysis.

OBJECTIVE: The purpose of this research was to study the stability internal consistency factor structure, and convergent and discriminate validity of the Hogan Empathy Scale (EM) when used longitudinally with occupational therapy students. METHOD: More than 300 occupational therapy students completed the EM once; 192 completed it twice over a 12-month interval; and 56 completed a third administration at intervals ranging from 3 years to 6 years. The Fieldwork Performance Evaluation (FWPE) was rated twice for students after fieldwork rotations in the occupational therapy program. Data on grade-point average, gender, and age were collected. RESULTS: Stability was estimated at .41 over a 12-month interval and from .30 to .38 over longer intervals. Internal consistency was estimated at .57, and factor structures hypothesized previously were not replicable. Students' biographical variables explained only trivial amounts of variance in EM scores in regression equations (R = .08 and .21). Correlations between EM and FWPE scores did not support convergent validity (r = -. 01-.18). CONCLUSION: The reliability estimates for the EM as a measure of a trait-like construct are not encouraging and do not replicate previous estimates. Validity evidence was equally disappointing, raising questions about what the EM is measuring and cautioning against its continued, uncritical use as a measure of empathy.

Empathy↗
PubMed2004

Validating the assumption to the interference approximation by use of measurements of absorption efficiency and hindered scattering in dense suspensions.

Frequency domain photon migration (FDPM) measurements were employed to accurately quantify optical properties of both the suspending fluid and particles within dense polystyrene suspensions of 143- or 226-nm mean diameter at varying concentrations (5-30% by volume). The measured absorption coefficients varied linearly with particle volume fraction whereas the isotropic scattering coefficients varied nonlinearly in agreement with the prediction that utilizes the hard-sphere structure factor model. These results validate the interference approximation of light scattering to describe light propagation accurately within dense suspensions. Furthermore, owing to the accuracy of FDPM absorption measurements, the imaginary refractive indices for both particles and their suspending fluid were determined and were found to compare favorably with literature values.

Light↗
PubMed2006

Development and psychometric evaluation of the ICIQ Vaginal Symptoms Questionnaire: the ICIQ-VS.

OBJECTIVES: To develop and validate a self-completion questionnaire for comprehensive assessment of the severity and impact of vaginal symptoms and related sexual matters, particularly those attributed to pelvic organ prolapse. To provide an instrument that can characterise the severity of these symptoms, measure their impact and evaluate treatment outcome. DESIGN: Prospective development of the content of the questionnaire and testing of its psychometric properties including validity. SETTING: Two hospital-based urogynaecology clinics and one community general practice in the South of England. POPULATION: One hundred and forty-one urogynaecology clinic attendees with varying degrees of pelvic organ prolapse and 77 randomly selected women registered with a general practice. METHODS: The questionnaire was developed through a literature review, consultation with clinicians and health scientists and structured interviews with patients. Content validity, construct validity, stability, internal consistency and sensitivity to change were examined by comparing the responses from the urogynaecology clinic with responses from the general community. Sensitivity to change was assessed using responses from women undergoing surgical treatment for pelvic organ prolapse before and 3 months after surgery. A final version of the questionnaire was obtained after factor analysis to assist item reduction and refinement of the scoring system. MAIN OUTCOME MEASURES: Content validity, construct validity, stability (test-retest reliability), internal consistency and sensitivity to change. RESULTS: The questionnaire exhibited good validity, reliability and sensitivity to change. Excellent internal consistency was demonstrated for vaginal (Cronbach's alpha 0.79) and sexual (Cronbach's alpha 0.84) symptoms. Reliability was good. The questionnaire was able to identify changes in symptoms following surgical treatment. The final ICIQ-VS questionnaire had 14 items and a simple scoring system. CONCLUSION; The ICIQ-VS self-completion questionnaire meets the need for a robust instrument for assessing a range of vaginal and sexual symptoms, in particular those of pelvic organ prolapse. It will be of use in both routine clinical practice and epidemiological research, particularly when there is a need to assess the severity of these symptoms or the efficacy of treatment.

Adult↗
PubMed2026

Trustworthy Agentic AI in Bioinformatics: From Workflow Automation to Traceable and Validated Biological Inference.

Agentic artificial intelligence is extending bioinformatics beyond conversational assistance by enabling systems to select tools, execute code, revise analytical plans, and interpret biological data. These capabilities may accelerate research, but they also redistribute decisions that determine whether biological conclusions are valid. We conducted a targeted, structured PubMed search in July 2026 and identified 11 peer-reviewed agentic bioinformatics systems for descriptive review based on predefined eligibility criteria for analytical decision-making, tool or code execution, iterative evaluation, or coordinated agent activity. The evidence base covered single-cell transcriptomics, microbial genomics, cancer genomics, and omics applications, together with methodological literature on reproducibility and biological validation. We examined how current systems report delegated authority, provenance, validation, evidence, abstention, and human oversight. Existing platforms implement safeguards such as sandboxed execution, restricted commands, interaction logs, evidence identifiers, automated checks, critic agents, quality scores, and expert assessment. However, published reports rarely provide a connected account linking the original biological question to samples, reference resources, analytical decisions, computational actions, statistical results, supporting evidence, validation outcomes, and final claims. We distinguish inherited bioinformatics errors, errors amplified through autonomous action, and emergent failures arising from memory, retrieval, tool interaction, or agent coordination. We further propose a multidimensional decision-rights profile, consequence-sensitive validation gates, and a claim-to-evidence provenance architecture organized through the Traceable History of Research Evidence, Agent Actions, and Decisions in Bioinformatics (THREAD-Bio) framework. Illustrative cases show that technically successful execution may still support misleading inference. Trustworthy agentic bioinformatics therefore requires claims to remain reconstructible, challengeable, validated, and proportionate to the evidence.

accountable autonomy↗
PubMed1997

The relationship of patient-administered outcome assessments to quality of life and physician ratings: validity of the BASIS-32.

The reliability and validity of a patient-administered version of the Behavior and Symptom Identification Scale (BASIS-32) was compared to the original interviewer-administered version. The construct validity of BASIS-32 subscales was assessed by examining their relationship with functional and satisfaction quality of life and physician ratings of functional and clinical status. A total of 361 acute psychiatric inpatients were given a self-administered BASIS-32, nurse-administered Lehman's Quality of Life Interview (QOLI), and Psychiatrist Assessment Form at admission and discharge. The original factor structure, internal consistency reliability, discriminant validity, and sensitivity to change were replicated. The patient-administered BASIS-32 is equally as reliable and valid as the interview. Construct validity analyses revealed that functional and satisfaction QOLI indices were moderately related to the BASIS-32 in the hypothesized directions. All satisfaction scales were associated with significantly less severity. Physician ratings were only mildly related to the subscales. The BASIS-32 used in outcome assessments with inpatients provides important and unique perspectives on functional and clinical status that are not tapped by clinician-rated assessments.

Inpatients↗
PubMed2001

Structural criteria for the rational design of selective ligands. 3. Quantitative structure-stability relationship for iron(III) complexation by tris-catecholamide siderophores.

We present an extended MM3 model for catecholamide ligands and their Fe(3+) complexes and the application of this model to understand how ligand architecture effects Fe(3+) binding affinity. Force field parameters were fit to geometries and energies from electronic structure calculations, and to crystal structure data. Optimized geometries are reported for phenol, acetamide, the phenol-phenol dimer, the acetamide-phenol dimer, and N-methylsalicylamide (HMSA) at the BLYP/DZVP2/A2 level of theory. Optimized geometries and relative energies are reported for the pseudo-octahedral ground state and the trigonal planar transition state of [Fe(CAT)(3)](3)(-) at the VWN/DZVP2/A1 level of theory. The MM3 model is validated by comparison of calculated structures with crystal structures containing 1,2-dihydroxybenzene (H(2)CAT) and 2,3-dihydroxy-N-methylbenzamide (H(2)MBA) fragments, crystal structures of [Fe(CAT)(3)](3)(-) and tris-catecholamide Fe(3+) complexes, and comparison of MM3 (6.8 kcal/mol) and VWN (5.9 kcal/mol) barriers for intramolecular octahedral inversion in [Fe(CAT)(3)](3)(-). The MM3 model also rationalizes the higher inversion barrier (14 to 18 kcal/mol) reported for [Ga(N,N-diisopropylterephthalamide)(3)](3)(-) ([Ga(DIPTA)(3)](3)(-)). Conformational searches were performed on enterobactin (H(6)ENT), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)-2,4,6-triethylbenzene (H(6)EMECAM), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)-2,4,6-trimethylbenzene (H(6)MMECAM), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)benzene (H(6)MECAM), and 1,5,9-N,N',N' '-tris(2,3-dihydroxybenzoyl)cyclotriazatridecane (H(6)-3,3,4-CYCAM) and Fe(3+) complexes with each of these ligands. A conformational search also was done on the Fe(3+) complex with the 2,2',2' '-tris(2,3-dihydroxybenzamido)triethylammonium cation (H(7)TRENCAM(+)). The relationship between calculated steric energies and measured thermodynamic quantities is discussed, and linear correlations between formation constants and steric energy differences are reported. Extrapolation to zero strain predicts formation constants 8 +/- 5 orders of magnitude higher than that exhibited by ENT (10(49)) are possible. This prediction is supported by a formation constant of 10(63) estimated from the formation constant of [Fe(2,3-dihydroxy-N,N-dimethylbenzamide)(3)](3)(-) ([Fe(DMBA)(3)](3)(-)) by considering the entropic consequences of connecting three DMBA ligands to a rigid backbone. Structural criteria for the identification of improved tris-catecholate ligand architectures are presented.

Algorithms↗
PubMed2004

A fresh look at the wolf-pack theory of companion-animal dog social behavior.

A popular perspective on the social behavior of dogs in multiple-dog households sees the dogs' behavior as reflecting the sociobiological laws of the rigidly structured dominance hierarchy that has been described for wolf packs. This view suggests that aggression problems among dogs are natural expressions of conflict that arise whenever dominance status is in contention. One recommended solution has been for the owner to endorse and enforce a particular dominance hierarchy because, on the wolf pack model, aggression is minimized when the structure of the hierarchy is clear, strong, and stable. This article questions the validity of this perspective on 2 principal grounds. First, because it does not seem to occur in the wild, this article suggests the strong dominance hierarchy that has been described for wolves may be a by-product of captivity. If true, it implies that social behavior--even in wolves--may be a product more of environmental circumstances and contingencies than an instinctive directive. Second, because feral dogs do not exhibit the classic wolf-pack structure, the validity of the canid, social dominance hierarchy again comes into question. This article suggests that behavioral learning theory offers another perspective regarding the behavior of dogs and wolves in the wild or in captivity and offers an effective intervention for aggression problems.

Animals↗
PubMed2006

Excess electron localization sites in neutral water clusters.

We present approximate pseudopotential quantum-mechanical calculations of the excess electron states of equilibrated neutral water clusters sampled by classical molecular dynamics simulations. The internal energy of the clusters are representative of those present at temperatures of 200 and 300 K. Correlated electronic structure calculations are used to validate the pseudopotential for this purpose. We find that the neutral clusters support localized, bound excess electron ground states in about 50% of the configurations for the smallest cluster size studied (n = 20), and in almost all configurations for larger clusters (n > 66). The state is always exterior to the molecular frame, forming typically a diffuse surface state. Both cluster size and temperature dependence of energetic and structural properties of the clusters and the electron distribution are explored. We show that the stabilization of the electron is strongly correlated with the preexisting instantaneous dipole moment of the neutral clusters, and its ground state energy is reflected in the electronic radius. The findings are consistent with electron attachment via an initial surface state. The hypothetical spectral dynamics following such attachment is also discussed.

Journal Article↗
PubMed2005

Phylogeography of an east Australian wet-forest bird, the satin bowerbird (Ptilonorhynchus violaceus), derived from mtDNA, and its relationship to morphology.

Australian wet forests have undergone a contraction in range since the mid-Tertiary, resulting in a fragmented distribution along the east Australian coast incorporating several biogeographical barriers. Variation in mitochondrial DNA and morphology within the satin bowerbird was used to examine biogeographical structure throughout almost the entire geographical extent of these wet forest fragments. We used several genetic analysis techniques, nested clade and barrier analyses, that use patterns inherent in the data to describe the spatial structuring. We also examined the validity of the two previously described satin bowerbird subspecies that are separated by well-defined biogeographical barriers and tested existing hypotheses that propose divergence occurs within each subspecies across two other barriers, the Black Mountain corridor and the Hunter Valley. Our data showed that the two subspecies were genetically and morphologically divergent. The northern subspecies, found in the Wet Tropics region of Queensland, showed little divergence across the Black Mountain corridor, a barrier found to be significant in other Wet Tropics species. Biogeographical structure was found through southeastern Australia; three geographically isolated populations showed genetic differentiation, although minimal divergence was found across the proposed Hunter Valley barrier. A novel barrier was found separating inland and coastal populations in southern New South Wales. Little morphological divergence was observed within subspecies, bar a trend for birds to be larger in the more southerly parts of the species' range. The results from both novel and well-established genetic analyses were similar, providing greater confidence in the conclusions about spatial divergence and supporting the validity of these new techniques.

Analysis of Variance↗
PubMed2006

Prediction of binding affinities between the human amphiphysin-1 SH3 domain and its peptide ligands using homology modeling, molecular dynamics and molecular field analysis.

The SH3 domain of the human protein amphiphysin-1, which plays important roles in clathrin-mediated endocytosis, actin function and signaling transduction, can recognize peptide motif PXRPXR (X is any amino acid) with high affinity and specificity. We have constructed a complex structure of the amphiphysin-1 SH3 domain and a high-affinity peptide ligand PLPRRPPRA using homology modeling and molecular docking, which was optimized by molecular dynamics (MD). Three-dimensional quantitative structure-affinity relationship (3D-QSAR) analyses on the 200 peptides with known binding affinities to the amphiphysin-1 SH3 domain was then performed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). The best CoMSIA model showed promising predictive power, giving good predictions for about 95% of the peptides in the test set (absolute prediction errors less than 1.0). It was used to validate peptide-SH3 binding structure and provide insight into the structural requirements for binding of peptides to SH3 domains. Finally, MD simulations were performed to analyze the interaction between the SH3 domain and another peptide GFPRRPPPRG that contains with the PXRPXsR (s represents residues with small side chains) motif. MD simulations demonstrated that the binding conformation of GFPRRPPPRG is quite different from that of PLPRRPPRAA especially the four residues at the C terminal, which may explain why the CoMSIA model cannot give good predictions on the peptides of the PXRPXsR motif. Because of its efficiency and predictive power, the 3D-QSAR model can be used as a scoring filter for predicting peptide sequences bound to SH3 domains.

Amino Acid Sequence↗
PubMed2005

Photolabeling study of the ligand binding domain of natriuretic peptide receptor A: development of a model.

Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are loop-shaped peptidic hormones that have multiple actions on body fluid homeostasis. Their physiological effects are mediated through the activation of their receptor, natriuretic peptide receptor A (NPRA). This receptor is a member of the membrane guanylyl cyclase family and catalyzes cyclic guanosine monophosphate (cGMP) production following its activation. To map the binding site of human NPRA, we applied the methionine proximity assay method to this receptor. We photolabeled NPRA mutants, presenting a single methionine in the binding domain of the receptor, and used benzoylphenylalanine- (Bpa-) substituted peptides at positions 0, 3, 18, 26, and 28 of the ligand. We identified that the N-terminus of the peptide is interacting with the region between Asp(177) and Val(183) of the receptor. Arg(3) is interacting in the vicinity of Phe(172). Leu(18) binds close to Val(116). Phe(26) binds in the vicinity of His(195), and the C-terminal Tyr(28) is located close to Met(173). We next proceeded with photolabeling of a dual Bpa-substituted peptide and showed that the N-terminus and Leu(18) interact with opposite receptor subunits. On the basis of our results, a molecular model of peptide-bound NPRA was developed by homology modeling with the C-type natriuretic peptide- (CNP-) bound natriuretic peptide receptor C (NPRC) crystal structure. The model has been validated by molecular dynamics simulations. Our work provides a rational basis for interpreting and predicting natriuretic peptide binding to the human NPRA.

Amino Acid Sequence↗
PubMed2004

Prediction of alpha-turns in proteins using PSI-BLAST profiles and secondary structure information.

In this paper a systematic attempt has been made to develop a better method for predicting alpha-turns in proteins. Most of the commonly used approaches in the field of protein structure prediction have been tried in this study, which includes statistical approach "Sequence Coupled Model" and machine learning approaches; i) artificial neural network (ANN); ii) Weka (Waikato Environment for Knowledge Analysis) Classifiers and iii) Parallel Exemplar Based Learning (PEBLS). We have also used multiple sequence alignment obtained from PSIBLAST and secondary structure information predicted by PSIPRED. The training and testing of all methods has been performed on a data set of 193 non-homologous protein X-ray structures using five-fold cross-validation. It has been observed that ANN with multiple sequence alignment and predicted secondary structure information outperforms other methods. Based on our observations we have developed an ANN-based method for predicting alpha-turns in proteins. The main components of the method are two feed-forward back-propagation networks with a single hidden layer. The first sequence-structure network is trained with the multiple sequence alignment in the form of PSI-BLAST-generated position specific scoring matrices. The initial predictions obtained from the first network and PSIPRED predicted secondary structure are used as input to the second structure-structure network to refine the predictions obtained from the first net. The final network yields an overall prediction accuracy of 78.0% and MCC of 0.16. A web server AlphaPred (http://www.imtech.res.in/raghava/alphapred/) has been developed based on this approach.

Amino Acid Sequence↗
PubMed2001

Non-competitive GABA antagonists: probing the mechanisms of their selectivity for insect versus mammalian receptors.

A great variety of non-competitive antagonists of ionotropic gamma-aminobutyric acid (GABA) receptors have been reported. While they are structurally diverse, there are common features in their structures. Thus, it was hypothesized that they bind to an identical site in different or overlapping orientations, and this hypothesis was validated by three-dimensional structure-activity relationship (3D-QSAR) analysis using receptor-binding data. Meanwhile, although most antagonists are highly toxic to both vertebrates and invertebrates, several classes of antagonists, such as nor-diterpene lactone picrodendrins, phenyl heterocyclic compounds and disubstituted bicyclophosphorothionates, were found to exhibit selectivity for housefly versus rat GABA receptors. To probe their selectivity mechanisms, the 3D-QSAR method was applied to the three classes of antagonists. This revealed several important differences that might be related to the selectivity of antagonists between the structures of the non-competitive antagonist-binding sites of housefly and rat GABA receptors.

Animals↗
PubMed2005

The Chinese Medical Interview Satisfaction Scale-revised (C-MISS-R): development and validation.

BACKGROUND: The Medical Interview Satisfaction Scale (MISS) measures patient consultation satisfaction. We validated a translated short-form of the original MISS on Hong Kong Chinese women with breast cancer. METHODS: The four highest scoring MISS Cognitive and Affective sub-scales items were administered in Chinese (C-MISS) to 224 female out patients. Phrasing revisions (C-MISS-R) were tested on 82 women. Random split tested factor structure stability. Convergent, divergent and criterion validation against other instruments was performed on 405 women. RESULTS: Two-factors accounted for 61.7% of variance but factor loadings differed from the original. Phrasing revision increased Affective sub-scale item-item correlations exceeding 0.3-64%. Two factors matching those of the original MISS, accounting for 65.2% of variance, explained 36.6% (Cognitive) and 28.8% (Affective) of variance, respectively. Alpha was 0.84,0.74 and 0.83 for the Cognitive and Affective sub-scales and total respectively. Correlations of difficulties with treatment decision making (r = -0.298), Self-efficacy (r = 0.194), optimism (r = 0.33), psychological morbidity (r = -209), marital status, education and age indicated acceptable validity. Test-retest reliability was 0.410. DISCUSSION: The Chinese MISS-Revised (C-MISS-R) has suitable factor structure and psychometric properties for use in consultation studies among Chinese female populations. Further validation is needed for males.

Aged↗
PubMed2006

A patient-based questionnaire to assess outcomes of foot surgery: validation in the context of surgery for hallux valgus.

BACKGROUND: A patient-based outcome measure with good measurement properties is urgently needed for use in clinical trials of foot surgery. METHODS: We evaluated an existing foot pain and disability questionnaire (the Manchester Foot Pain and Disability Questionnaire) for its suitability as an outcome measure in the context of hallux valgus corrective surgery. Interviews with patients led to initial changes, resulting in 20 candidate questionnaire items with five response categories each. These were tested in a prospective study of 100 patients (representing 138 foot operations) undergoing hallux valgus corrective surgery. Analysis of underlying factor structure, dimensionality, internal reliability, construct validity and responsiveness of the questionnaire items in relation to (i) SF-36 general health survey and (ii) American Orthopaedic Foot & Ankle Society (AOFAS) hallux clinical scale resulted in a final 16 item questionnaire (the 'Manchester-Oxford Foot Questionnaire' (MOXFQ)), consisting of three domains/scales: 'Walking/standing' (seven items), 'Pain' (five items) and 'Social interaction' (four items) each having good measurement properties. All three domains were unidimensional. CONCLUSIONS: The new 16-item MOXFQ has good measurement properties in the context of outcomes assessment of surgery for hallux valgus. Future studies should assess the MOXFQ in the context of surgery for other foot and ankle conditions.

Adult↗