David Karlsson | Search PubMed

PubMed2002

A comparison of diagnosis capture from medical records, self-reports, and drug registrations: a study in individuals 80 years and older.

BACKGROUND AND AIMS: Reports of diseases and health problems vary as a function of the information source. In the present study we compared the capture of information on morbidity using medical records, self-reports, and drug registrations. METHODS: A concurrent review of medical records, self-reports, and registration of marker drugs was conducted to determine diagnosis for 44 common diseases. Diagnoses from the various sources were uniformly classified according to ICD-10. The study included a sample of 702 individuals, aged 80 and older, enrolled in population-based longitudinal studies. RESULTS: The morbidity rates differed considerably across the used sources. Although medical records captured most of the morbidity, self-reports offered supplemental information especially for less objective health problems. Marker drugs typically confirmed information in the records, but only for a limited number of diseases. DISCUSSION: In studies of aging and health, a thorough review of medical records and a concurrent evaluation of self-reports and marker drugs represent a valuable strategy for portraying morbidity. This strategy goes beyond the use of a single source like self-reports, and provides better estimates of health conditions in the elderly.

Aged↗

PubMedDate not supplied

Electronic speckle pattern interferometry: a tool for determining diffusion and partition coefficients for proteins in gels.

The aim of this study was to demonstrate electronic speckle pattern interferometry (ESPI) as a powerful tool in determining diffusion coefficients and partition coefficients for proteins in gels. ESPI employs a CCD camera instead of a holographic plate as in conventional holographic interferometry. This gives the advantage of being able to choose the reference state freely. If a hologram at the reference state is taken and compared to a hologram during the diffusion process, an interferometric picture can be generated that describes the refraction index gradients and thus the concentration gradients in the gel as well as in the liquid. MATLAB is then used to fit Fick's law to the experimental data to obtain the diffusion coefficients in gel and liquid. The partition coefficient is obtained from the same experiment from the flux condition at the interface between gel and liquid. This makes the comparison between the different diffusants more reliable than when the measurements are performed in separate experiments. The diffusion and partitioning coefficients of lysozyme, BSA, and IgG in 4% agarose gel at pH 5.6 and in 0.1 M NaCl have been determined. In the gel the diffusion coefficients were 11.2 +/- 1.6, 4.8 +/- 0.6, and 3.0 +/- 0.3 m(2)/s for lysozyme, BSA, and IgG, respectively. The partition coefficients were determined to be 0.65 +/- 0.04, 0.44 +/- 0.06, and 0.51 +/- 0.04 for lysozyme, BSA, and IgG, respectively. The current study shows that ESPI is easy to use and gives diffusion coefficients and partition coefficients for proteins with sufficient accuracy from the same experiment.

Animals↗