Whitaker test

Fig. 1.1.10. Antegrade pyelography combined with the Whitaker test on general anesthesia in a 6-month-old baby. No reflux. Slight dilatation on ultrasound and IVU. Diuresis renography had not been conclusive, and the Whitaker test showed obstruction at the ureteropelvic junction. Surgery was subsequently performed...

Fig. 1.1.11. Antegrade pyelography combined with the Whitaker test. Patient is in the prone position on general anesthesia. A Foley catheter is placed in the bladder and pressure is monitored. Two needles are placed in the renal pelvis with sonographic guidance. One is used to infuse contrast medium on either constant pressure perfusion or constant flow perfusion. The other one is connected with a pressure transducer. (Drawing by V. Genne, MD)...

Fig. 1.1. 12. Antegrade pyelography combined with the Whitaker test. Intermittent obstruction at the ureteropelvic junction in a child with equivocal results on diuresis renography. Constant flow renal perfusion (5 cc/min). Transient peak in pelvic and differential pressures are shown and complete the criteria for obstruction...

The Whitaker test or pressure measurements after urinary tract nephrostomy are used with some success in selected cases (Peters 1995). It necessitates sedation and the placement of a nephrostomy tube. It can therefore not be used in every case. 

In rare instances, obstruction caused by a fungus ball may be treated with a combination of percutaneous nephrostomy and infusion of amphotericin (Fig. 26.3) (Matsumoto et al. 1990). In asymptomatic children with hydronephrosis, antegrade pyelography and pressure measurement (Whitaker test) maybe performed prior to surgical or endouro-logic correction to document the level and nature of the obstruction. Finally, percutaneous nephrostomy... 

Fig. 26.2. Teenage girl with a dilated renal pelvis and equivocal Lasix renogram after a dismembered pyeloplasty. Whitaker test performed using a 2 needle technique demonstrating an enlarged renal pelvis due to an UPJ obstruction...

Ticktin A., Whitaker B. J., McCaffery A. J. Computational test of fitting laws of rotational energy transfer, Chem. Phys. Lett. 139, 571-5 (1987). 

TB Whitaker, JW Dickens. Evaluation of the peanut administrative committee testing program for aflatoxin in shelled peanuts. Peanut Sci 6 7-9, 1979. 

TB Whitaker, F Giesbrecht, J Wu. Suitability of several statistical models to simulate observed distribution of sample test results in inspections of aflatoxin-contaminated peanut lots. J AOAC Int... 

TB Whitaker, J Springer, PR Defize, W De Koe, R Coker. Evaluation of sampling plans used in the United States, United Kingdom, and The Netherlands to test raw shelled peanuts for aflatoxins. J AOAC Int 78(4) 1010-1018, 1995. 

Leovic, K.W., Whitaker, D.A., Northeim C. and Sheldon L.S. (1998) Evaluation of test method for measuring indoor air emissions from dry-process photocopiers. Journal of Air sj Waste Management Association, 48, 915-23. 

The Multiple Sclerosis Functional Composite (MSFC) was developed by the MS Consortium (Whitaker et al., 1995) for evaluating disabilities ranging from motor function to cognitive changes and to replace the EDSS. The three tools included in the MSFC are a timed 25 foot walk, the 9-hole peg test for hand dexterity and the Paced Auditory Serial Addition Test (PASAT). The MSFC is a quandfiable measure of disability but ten years later, it is sdll infrequently incorporated as a primary outcome measure because of the increased time element necessary to validate the individual tests and the dme necessary for their adminisd adon. 

With respect to the definition of the LOD of AFT, other methodological approaches should be tested, such as uniform, normal or lognormal distributions or methods based on quantiles (see, for example, Harter Moore, 1966 Reid, 1981 Roger Peacock, 1982 Gilliom Helsel, 1986 Green Crowley, 1986 Travis Land, 1990 Hecht Honikel, 1995 Vlachonikolis Marriott, 1995 Giersbrecht Whitaker, 1998 Korn Tyler, 2001). 

To evaluate the total uncertainty among sample test results, it is recommended that the procedure described by Ozay et al. (2006) and Whitaker et al. (2006) or a similar procedure be followed. 

Vargas, E.A., Whitaker, T.B., dos Santos, E.A., Slate, A.B., Lima, F.B. Franca, R.C.A. (2006b) Testing green coffee for ochratoxin A, Part II Observed distribution of ochratoxin A test results. J. AOAC Int 88, 780-787. 

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