Non-recommended variable length

b Bedeoan

on March 26, 2012

Hello all,

At a validation of a dataset using the latest version of Validator, I get multiple Warnings of the following form: "Non-recommended variable length" for Rules: SD1057, SD1058 and SD1059.

As an example, Rule SD1058 says that: "The length of Planned Arm Code variable (ARMCD) is expected to be 20".

Shouldn't this be: "The length of Planned Arm Code variable (ARMCD) is expected to be LESS THAN 20"? (see caps). Same for the other rules. SEND specs don't say anything about a fixed size of 8, 20 or 40 chars; only says that some variables' content should be LESS THAN 8/20/40.

Am I missing something?

Thank you!

Forums: Validation Rule Suggestions

s Sergiy

on March 26, 2012

This is metadata rule

Hi! This rule checks the variable length, but not the length of a ARMCD value. The maximum value length for ARMCD is 20 characters. It could be less or equal 20 chars. FDA encourages you to 1. not use unreasonably long variable length (e.g., 200 chars for baseline flag (--BLFL)) 2. have consistently in variables' lengths across a whole submission (to avoid potential truncation problems during data pooling/manipulation across domains and studies) It’s quite challenging to check this for all data variables in the OpenCDISC Validator Community version (it’s done in OC Enterprise version, which performs cross-standards and cross-studies validation). However it’s quite straightforward for variables with standards limitations for variable value. A maximum allowed length for ARMCD value is 20 chars. Therefore the expected variable length is also 20 chars. It’s a minimal safe variable length to keep all possible values across all other studies in your submission. Regards, Sergiy

b Bedeoan

on March 27, 2012

Re: This is metadata rule

Thank you for your detailed answer, Sergiy.

The conclusion is that for the ARMCD variable there has to be 20 chars allocated in the .xpt file (the column listed as "Length" in dataset's preview from SAS Universal Viewer).

As a general rule, all SEND variables must respect the length rules specified by the SEND specifications (CDISC equivalent rules: SD1054, SD1057, SD1058, SD1059).

Best regards,

Amelia