Interobserver agreement and validity of bedside 'positive signs' for functional weakness, sensory and gait disorders in conversion disorder: a pilot study.

BACKGROUND: Conversion disorder (CD) is no longer a diagnosis of exclusion. The new DSM-V criteria highlight the importance of 'positive signs' on neurological examination. Only few signs have been validated, and little is known about their reliability. OBJECTIVE: The aim was to examine the clinical value of bedside positive signs in the diagnosis of CD presenting with weakness, gait or sensory symptoms by assessing their specificity, sensitivity and their inter-rater reliability. PATIENTS AND METHODS: Standardised video recorded neurological examinations were performed in 20 consecutive patients with CD and 20 'organic' controls. Ten previously validated sensory and motor signs were grouped in a scale. Thirteen additional motor/sensory 'positive signs', 14 gait patterns and 1 general sign were assessed in a pilot validation study. In addition, two blinded independent neurologists rated the video recordings to assess the inter-rater reliability (Cohen's κ) of each sign. RESULTS: A score of ≥4/14 on the sensory motor scale showed a 100% specificity (CI 85 to 100) and a 95% sensitivity (CI 85 to 100). Among the additional tested signs, 10 were significantly more frequent in CD than controls. The interobserver agreement was acceptable for 23/38 signs (2 excellent, 10 good, 11 moderate). CONCLUSIONS: Our study confirms that six bedside 'positive signs' are highly specific for CD with good-excellent inter-rater reliability; we propose to consider them as 'highly reliable signs'. In addition 13 signs could be considered as 'reliable signs' and six further signs as 'suggestive signs' while all others should be used with caution until further validation is available.

Tolerance and Relative Utility: Two Proposed Indices for Comparing Change in Clinical Measurement Noise Between Different Populations (Repeatability) or Measurement Methods (Agreement).

Reaching a consensus in terms of interchangeability and utility (i.e., disease detection/monitoring) of a medical device is the eventual aim of repeatability and agreement studies. The aim of the tolerance and relative utility indices described in this report is to provide a methodology to compare change in clinical measurement noise between different populations (repeatability) or measurement methods (agreement), so as to highlight problematic areas. No longitudinal data are required to calculate these indices. Both indices establish a metric of least to most effected across all parameters to facilitate comparison. If validated, these indices may prove useful tools when combining reports and forming the consensus required in the validation process for software updates and new medical devices.

Treatment of Retinoblastoma in 2015: Agreement and Disagreement.

The management of intraocular retinoblastoma is rapidly changing, and even recent reviews on the subject are behind existing practices. The 4 authors of this report collectively represent their management strategies with an emphasis on areas of agreement and disagreement. Ophthalmic artery chemosurgery and intravitreous chemotherapy have completely replaced external beam radiotherapy, reduced the use of systemic chemotherapy, and diminished enucleations by 90% without evidence of compromising patient survival.

Are Public Private Partnerships that Rigid ? And Why ? : Evidence from Toll Road Concession Contracts

Transport concession contracts are commonly said to be standardized and too rigid. They would not allow public authorities to adapt them to evolving context and circumstances. This paper aims at challenging this view and, more particularly, the view that contractual rigidity for transport concessions is exogenous. Using a transaction cost framework, we disentangle between three main determinants of contractual rigidity: traffic uncertainty; connivance between contracting parties; quality of the institutional environment. Using an original database of toll road concession contracts, we observe a great variety of provisions for toll adjustment. We find that these exogenous determinants significantly influence contractual choices.