Professional Detailing2 min read

Build a Data Dictionary for Coating Trials Before Combining Spreadsheets

Define trial fields, units, sample IDs and missing values before combining coating spreadsheets or calculating comparison scores.

Updated · NANOLAB Knowledge

A data dictionary defines what each field in a trial record means. It prevents apparently similar columns from being combined when they actually contain different units, methods or event definitions. This matters as soon as more than one person records results.

Define the important fields

For each column, specify its name, meaning, unit, allowed values and missing-value convention. “Cure time” needs a start and endpoint. “Temperature” needs to identify air, liquid or substrate. “Pass” needs an acceptance criterion and method revision.

An illustrative field called elapsed_hours could mean hours since application ended, while another sheet uses hours since the vehicle arrived. Combining them would create a plausible-looking but incorrect dataset. A clear definition prevents that error.

Keep identifiers stable

Use a unique sample ID that survives renaming and follow-up visits. Store product code, batch and surface identity in their own fields. Avoid encoding all information in a free-text sample name that staff must repeatedly interpret.

Keep dates in an unambiguous format and preserve the original time zone when time of day matters. Use explicit missing values rather than zero unless zero is the actual observation.

Separate raw observations from calculations

Retain measured values in one set of fields and derived rates, percentages or scores in another. Document the formula and version used for each calculation. This allows a corrected formula to be applied without overwriting the original evidence.

Before merging supplier or workshop files, compare their dictionaries. Resolve differences in units and definitions explicitly. A small documented conversion is better than silently forcing every column into the same label. The result is a trial record that can be checked, updated and understood by someone who did not attend the original application.

Related guidance

For product-specific application instructions, consult NANOLAB technical documentation or ask about your surface and intended use.