Culture Bottle Positivity Timeline

Track culture alarm delays and still-unalarmed bottles using explicit observation time; alarm timing alone does not identify contamination.

Description

Culture-bottle time to an alarm describes an observed detection timeline.

Culture-bottle time to an alarm describes an observed detection timeline. A bottle still without an alarm is pending evidence, distinct from a confirmed negative or a late positive.^[1]

Track culture alarm delays and still-unalarmed bottles using explicit observation time; alarm timing alone does not identify contamination.

When to use Culture Bottle Positivity Timeline

Use this tool to track culture alarm delays and still-unalarmed bottles using explicit observation time; alarm timing alone does not identify contamination.

Prepare the sample, count, growth or assay measurements requested by this tool. Confirm units, sampling periods and reporting bases; supply independently established comparison criteria where requested.

How to use Culture Bottle Positivity Timeline and understand its results

Prepare the sample, count, growth or assay measurements requested by this tool. Confirm units, sampling periods and reporting bases; supply independently established comparison criteria where requested.
Enter bottleIds, incubationStartHours, alarmHours, evaluationHour, maximumAlarmDelayHours using the field table and calculation rules, then run the tool.
Read positiveBottleIds, positivityDelaysHours, noAlarmBottleIds, delayedPositiveBottleIds. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
bottleIds	Bottle ids	list of string	Required
incubationStartHours	Incubation start hours	list of number	Required
alarmHours	Alarm hours	list of number	Required
evaluationHour	Evaluation hour	number; minimum: 0	Required
maximumAlarmDelayHours	Maximum alarm delay hours	number; minimum: 0	Required

Enter distinct bottle IDs with aligned nonnegative start hours and alarm hours, using −1 for no alarm. Starts and observed alarms must be chronological and no later than the nonnegative evaluation hour. Return positive IDs and delays, no-alarm IDs and positives strictly beyond the supplied nonnegative delay threshold. Equality is not delayed.

Paired lists must be nonempty and have equal lengths.

delay=alarmHour−startHour; delayed if delay>maximumAlarmDelay

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
positiveBottleIds	Positive bottle ids	list of string
positivityDelaysHours	Positivity delays hours	list of number
noAlarmBottleIds	No alarm bottle ids	list of string
delayedPositiveBottleIds	Delayed positive bottle ids	list of string

json

{
  "input": {
    "bottleIds": [
      "A",
      "B",
      "C"
    ],
    "incubationStartHours": [
      0,
      1,
      2
    ],
    "alarmHours": [
      5,
      -1,
      10
    ],
    "evaluationHour": 12,
    "maximumAlarmDelayHours": 6
  },
  "output": {
    "positiveBottleIds": [
      "A",
      "C"
    ],
    "positivityDelaysHours": [
      5,
      8
    ],
    "noAlarmBottleIds": [
      "B"
    ],
    "delayedPositiveBottleIds": [
      "C"
    ]
  }
}

Limitations and assumptions

The tool does not infer contamination, organism identity or final culture negativity. Times share one origin and alarm timing depends on the assay and sample; no future alarm can be entered as observed.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Stationary Phase Window Audit: Screen the final growth-curve window for a caller-defined relative stability band, rather than equating one count with carrying capacity. For a complementary task, use Water Coliform Sample Compliance: Audit water-sample coliform observations against a supplied per-sample allowance, retaining tested volumes; nondetection is not guaranteed sterility.

References

Culture Bottle Positivity Timeline — tool.io

Similar or alternative tools

Stationary Phase Window Audit
Screen the final growth-curve window for a caller-defined relative stability band, rather than equating one count with carrying capacity.
Water Coliform Sample Compliance
Audit water-sample coliform observations against a supplied per-sample allowance, retaining tested volumes; nondetection is not guaranteed sterility.