[{"data":1,"prerenderedAt":258},["ShallowReactive",2],{"\u002Fblog\u002Fwhen-your-spreadsheet-starts-making-gmp-decisions":3},{"id":4,"title":5,"author":6,"body":7,"category":239,"date":240,"description":241,"draft":242,"excerpt":243,"extension":244,"heroImage":243,"heroImageAlt":243,"meta":245,"navigation":246,"path":247,"seo":248,"slug":243,"stem":249,"tags":250,"__hash__":257},"blog\u002Fblog\u002Fwhen-your-spreadsheet-starts-making-gmp-decisions.md","When Your Spreadsheet Starts Making GMP Decisions","QikSolve",{"type":8,"value":9,"toc":230},"minimark",[10,14,17,22,31,50,53,64,67,71,74,88,101,105,108,140,144,147,164,167,171,174,200,203,207,215,223],[11,12,13],"p",{},"Most GMP spreadsheets start life as simple registers. Somewhere along the way, a formula gets\nadded to save someone the trouble of checking a result against a specification by hand. That\nformula is usually welcomed as a convenience. It rarely gets treated as the moment the spreadsheet\nchanged category.",[11,15,16],{},"This article is a practical interpretation of that scenario, not a validation protocol or a\ndetermination that any specific spreadsheet is compliant. Your organisation's own risk assessment\nand quality system remain the controlling references.",[18,19,21],"h2",{"id":20},"the-scenario","The scenario",[11,23,24,25,30],{},"Building on the ",[26,27,29],"a",{"href":28},"\u002Fblog\u002Fcalibration-register-just-a-spreadsheet-validation","calibration register example",",\nimagine the same spreadsheet now also contains:",[32,33,34,38,41,44,47],"ul",{},[35,36,37],"li",{},"Calibration values",[35,39,40],{},"Specification limits",[35,42,43],{},"Pass\u002Ffail calculations",[35,45,46],{},"Equipment status calculations",[35,48,49],{},"Trending data",[11,51,52],{},"A typical formula looks like this:",[54,55,61],"pre",{"className":56,"code":58,"language":59,"meta":60},[57],"language-text","=IF(ABS(Result-Target)\u003C=Tolerance,\"PASS\",\"FAIL\")\n","text","",[62,63,58],"code",{"__ignoreMap":60},[11,65,66],{},"Simple to write, and easy to trust once it has \"always worked.\" But this formula is now making a\nGMP decision that a person previously made by comparing numbers manually.",[18,68,70],{"id":69},"the-spreadsheet-trap","The spreadsheet trap",[11,72,73],{},"Many organisations still describe a spreadsheet like this as \"just Excel.\" In practice, it now\ndetermines:",[32,75,76,79,82,85],{},[35,77,78],{},"Equipment status (in calibration or out of calibration)",[35,80,81],{},"Compliance status against specification",[35,83,84],{},"Whether an investigation should be triggered",[35,86,87],{},"Whether a batch, process, or piece of equipment is reviewed further",[11,89,90,91,95,96,100],{},"In our ",[26,92,94],{"href":93},"\u002Fblog\u002Fhidden-validation-cost-of-excel-registers-in-gmp","maturity model for GMP spreadsheets",",\nthis is a ",[97,98,99],"strong",{},"decision-support spreadsheet",": Level 2. It is no longer acting as a register. It is\nacting as a small GMP application, built without the requirements, risk assessment, or testing that\nwould normally accompany one.",[18,102,104],{"id":103},"why-validation-expectations-increase","Why validation expectations increase",[11,106,107],{},"Once a formula decides pass or fail, the questions an assessment needs to answer expand:",[32,109,110,116,122,128,134],{},[35,111,112,115],{},[97,113,114],{},"Requirements",": what is the formula supposed to do, and under what conditions?",[35,117,118,121],{},[97,119,120],{},"Risk assessment",": what happens if the formula is wrong, and how would the organisation notice?",[35,123,124,127],{},[97,125,126],{},"Formula verification",": has the formula been checked against known, expected results?",[35,129,130,133],{},[97,131,132],{},"Boundary testing",": what happens at the edge of tolerance, with a blank cell, a negative\nnumber, or a rounding difference?",[35,135,136,139],{},[97,137,138],{},"Traceability",": can a specific pass\u002Ffail decision be traced back to the values and formula\nversion that produced it?",[18,141,143],{"id":142},"what-an-auditor-might-ask","What an auditor might ask",[11,145,146],{},"A reasonable inspector or auditor reviewing a spreadsheet like this may ask:",[32,148,149,152,155,158,161],{},[35,150,151],{},"How were these formulae verified?",[35,153,154],{},"How do you know the results are accurate?",[35,156,157],{},"How are the specification limits controlled, and who can change them?",[35,159,160],{},"What happens if someone edits the formula by mistake, and how would you know?",[35,162,163],{},"Can you show me the version history for this file?",[11,165,166],{},"These are fair questions. A spreadsheet performing a GMP calculation deserves the same scrutiny\nthat any other tool making that decision would receive.",[18,168,170],{"id":169},"the-hidden-cost","The hidden cost",[11,172,173],{},"The cost of this stage is rarely visible on a project plan. It shows up as ongoing effort:",[32,175,176,182,188,194],{},[35,177,178,181],{},[97,179,180],{},"Review effort",", checking that formulas have not silently changed.",[35,183,184,187],{},[97,185,186],{},"Periodic review",", re-confirming the spreadsheet still does what it was built to do.",[35,189,190,193],{},[97,191,192],{},"Retesting",", whenever a specification limit, tolerance, or formula structure changes.",[35,195,196,199],{},[97,197,198],{},"Change control burden",", tracking who changed what, and when, in a tool that was never designed\nfor that purpose.",[11,201,202],{},"This effort accumulates quietly, and it tends to be highest for the spreadsheets that are relied on\nmost.",[18,204,206],{"id":205},"a-more-proportionate-path","A more proportionate path",[11,208,209,210,214],{},"The goal is not to panic and rebuild every spreadsheet with a formula in it. It is to recognise\nthat a decision-support spreadsheet needs a different level of evidence than a register, and to\ndecide, deliberately, whether Excel remains the right platform for that decision once the ongoing\neffort is counted.\n",[26,211,213],{"href":212},"\u002Fblog\u002Fwhy-sharepoint-can-be-easier-to-validate-than-excel","The Spreadsheet Trap: Why SharePoint Can Be Easier to Validate Than Excel","\ncompares that ongoing effort directly using the same calibration example.",[11,216,217,218,222],{},"If your spreadsheet can determine pass or fail status, it may require significantly more validation\nthan you expect. A ",[26,219,221],{"href":220},"\u002Fvalidate-quality-register","GMP spreadsheet assessment"," can help classify the\nrisk and identify what evidence is genuinely needed.",[11,224,225,229],{},[26,226,228],{"href":227},"\u002Fcontact","Book a discovery call"," to discuss a spreadsheet that has started making GMP decisions.",{"title":60,"searchDepth":231,"depth":231,"links":232},2,[233,234,235,236,237,238],{"id":20,"depth":231,"text":21},{"id":69,"depth":231,"text":70},{"id":103,"depth":231,"text":104},{"id":142,"depth":231,"text":143},{"id":169,"depth":231,"text":170},{"id":205,"depth":231,"text":206},"Compliance","2026-09-14","Once a spreadsheet calculates pass or fail, status, or trend, it is no longer just a register. A practical look at what validation, evidence, and audit questions change once formulas start deciding GMP outcomes.",false,null,"md",{},true,"\u002Fblog\u002Fwhen-your-spreadsheet-starts-making-gmp-decisions",{"title":5,"description":241},"blog\u002Fwhen-your-spreadsheet-starts-making-gmp-decisions",[251,252,253,254,255,256],"excel","gmp","validation","annex-11","spreadsheets","calibration","15gi7XMsxt1rfzHMyfV9tzoSNTwcx39RqxXOoeG2Xeo",1789388497148]