Maintaining Precursor Schemes for a Scheme

A precursor scheme is a scheme that must be process in the laboratory before one or more sequel schemes are processes. This typically includes analytical preparation scheme work that occur before analytical scheme work.

When an append or overwrite QC process is run on a job, where a QC sample is created and registered for a job scheme by a QC mask member that is flagged to propagate the QC sample, then if the job scheme is a precursor scheme of one or more other job schemes, based upon precursor scheme relationships between the master schemes, then the QC sample is registered to the sequel job schemes also.

A precursor sample scheme's state controls which sample schemes are available for batching and which sequel sample schemes may be expired for analysis.
• A precursor sample scheme's Ready Date can be used as a sample search criteria when searching for samples to batch.
• A precursor sample scheme's Completed Date is used to determine a sequel sample scheme's Warning Date and Expiry Date and sequel sample scheme analyte's Warning Date and Expiry Date, which can be used to lock sequel sample scheme analyte's cell in a workbook session.
• A precursor sample scheme defaults to the precursor scheme relationships contained within the master scheme, when both schemes are registered on the sample. When a scheme is registered on a sample, if an existing sample scheme is a precursor or sequel of the new sample scheme, then a precursor sample scheme relationship is established.
• A master scheme can have a list of precursor schemes, and one or more of those precursor schemes can be configured to be registered automatically when the sequel scheme is registered on the sample, as long as the precursor scheme is either a lab-scope scheme or an org-scope scheme that is enabled for laboratory use.
• Where more than one sample scheme is a precursor of a sequel sample scheme, when the sequel sample scheme is registered, the sample scheme's Precursor Scheme Code is set to the first precursor sample scheme, based on alphanumerical order, after which it can be updated to link to a different precursor sample scheme. A precursor scheme scenario could be that you do not want to include samples in the count for analysis until their preparation is at least started, or one sample scheme may have a varying preparation pathway, or different samples may have a different combination of precursor schemes and sequel schemes.
• When an org-scope scheme is registered on a lab-scope job, the master scheme from where precursor scheme relationships are determined is the enabled-scope scheme.

Sample Scheme Precursors

Sample scheme precursor relationships default to the scheme precursor relationships on the master scheme (from enabled-scope scheme precursor relationships when an org-scope scheme is registered, or from lab-scope scheme precursor relationships when a lab-scope scheme is registered), but may be maintained on sample schemes.

When a scheme is added to a sample (by not using a template sample, but adding the scheme from scratch):

• If the scheme has multiple precursor schemes that are flagged to be auto-registered, then these precursor schemes are added to the sample automatically and positioned before the sequel scheme, and the sequel sample scheme's precursor scheme link is set to the first precursor sample scheme (based on the alphanumeric sequence of scheme codes).
• If the scheme has only one precursor scheme that is flagged to be auto-registered, then the precursor scheme is added to the sample automatically and positioned before the sequel scheme, and the sequel sample scheme's precursor scheme link is set to that precursor sample scheme.
• If the scheme has no precursor schemes that are flagged to be auto-registered, but one or more of those precursor schemes are already registered on the sample, then the sequel sample scheme's precursor scheme link is set to the first precursor sample scheme (based on alphanumeric sequence of scheme codes).

When a sequel sample scheme has multiple precursor sample schemes, then the sequel sample scheme's precursor scheme link can be set to any of those precursor sample schemes that do not have any existing precursor schemes.

When schemes are imported then any precursor scheme records for sequel schemes are updated. When a scheme is selected for importing then any linked schemes or precursor schemes are included in the import.