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Unit standardization, automatic calculations, and dropdown menus are utilized on data entry forms in order to avoid data entry 'typos' and unit conversion errors.
| Unit Standardization » | Automatic Calculations » | Dropdown Menus » |
Unit Standardization
Data is stored in the USTUR database using a set of standardized units. Standardized bioassay units are compatible with IMBA software, allowing the researcher to easily import, plot, and analyze data. The USTUR database eliminates unit conversion errors by allowing the user to enter measured values as they appear in the hard file. MS Access then standardizes the units using pre-programmed conversion factors. Both the original (hard-file based) values and the standardized values are stored in the database.
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| The USTUR database minimizes unit conversion errors by standardizing reported values using pre-programmed conversion factors. |
The USTUR database uses the following standardized units, listed according by the tab in which each data type appears:
Incidents
No unit conversions are necessary.
Contamination
Activity – dpm or cpm
In Vitro
Activity – pCi
Excretion Rate – pCi/day
Total Blood Activity – pCi
Nuclide Mass – microgram
Sample Period – day
Volume – milliliter
Mass (wet) – gram
In Vivo
Activity – pCi
Air Monitoring
Concentration – pCi/cc or MPC
Sample Period – day
Work Site Assessments
Absorbed Dose – rad
Body/Organ Burdens – pCi
Dose – rem
(all three are displayed under 'Derived Values')
External
Absorbed Dose – rad
Dose Equivalent – rem
Exposure – R
(all three are displayed under 'Derived Values')
Treatment
Dosage – gram
Activity Removed – pCi
Automatic Calculations
In addition to standardizing units, the USTUR database automatically derives selected in vitro quantities based upon the user-entered hard file data.
Derived Activity
Reported sample activities and concentrations are converted into derived activities in pCi/sample. The basic equation used to calculate derived activity from the sample concentration is:
Derived Activity = Conc · Volume Collected
Detailed derived activity calculations
Excretion Rate
The USTUR database converts reported urine and fecal activities, uncertainties, MDAs, and decision levels into daily excretion rates in pCi/day. The basic equation used to calculate excretion rate is:
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Excretion Rate = Activity/Sample Period.
Detailed excretion rate calculations
Total Blood Activity
Reported blood sample activities, uncertainties, MDAs, and decision levels are scaled up to the total blood activity using the ICRP 89 total blood volume for an adult male, 5300 mL. The basic equation used to calculate total blood activity is:
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Total Blood Activity = Concentration · 5300 mL
Detailed total blood activity calculations
Effective Sample Period
The effective sample period is automatically calculated for all normalization types except for the 'Pooled' type where it must be manually entered and the 'Conc' type where the user can override the automatic calculation and manually enter the effective sample period. The equation used to calculate effective sample period for '24hr,' 'Timed,' and 'Conc' samples is:
Effective Sample Period = Collection End Time - Collection Start Time
The effective sample period is set to 1 day for the 'Sim24' normalization type, and it is left blank for 'Volume/Mass' and 'n.a.' normalization types since these sample types are inappropriate if the sample period is known.
The sample period must, by definition, equal 1 day for the '24hr' sample type. If the difference between a collection start and end time is not exactly equal to 1 day, then a warning message is displayed and the collection end time is recalculated as:
- Collection End Time = Collection Start Time + 1 day
Less Than MDA Checkbox
The 'Reported <MDA' checkbox on the In Vivo and In Vitro forms flags measurements that were reported to be less than MDA in the hardfile. It is automatically checked when the user enters a zero activity value and unchecked when a non-zero value or null is entered. The checkbox can also be manually checked or unchecked by the user.
Dropdown Menus
Consistent nomenclature, abbreviations, and spelling are extremely important in a database. Without them fields cannot be properly searched. For example, imagine searching for all wound measurements if the in vivo counts have been referred to as hand, wound, finger count, thumb, arm, etc. One can never be certain that he has searched for all phrases that might indicate a wound count. Dropdown menus are utilized throughout the USTUR database to eliminate 'typos' and ensure consistent nomenclature by forcing the user to select from a finite list of values.
This page was last updated on March 10, 2008. usturwebmaster@tricity.wsu.edu