last observed date

USAGE SUMMARY

The phrase "last observed date" is correct and usable in written English.
It can be used in contexts where you need to specify the most recent date something was seen or recorded, often in scientific, medical, or data reporting scenarios. Example: "The last observed date of the species in this region was recorded as June 15, 2022."

✓ Grammatically correct

Science

Human-verified examples from authoritative sources

Exact Expressions

4 human-written examples

For survival analysis, OS was measured from the start of treatment to death or last observed date alive (censored observation), and progression-free survival (PFS) was measured from the start of treatment to the date of progression or death, which ever occurred first, or last the date alive (censored observation).

British Journal of Cancer

These miners were treated as alive until last observed date and then censored.

British Journal of Cancer

The 111 participants who could not be matched to NDI-plus or Social Security Administration were considered alive until their last observed date and censored afterward.

Epidemiology

If a subject completed the study schedule, or discontinued the study without the subject experiencing the event, the subject was treated as a censored case at the subject's last observed date.

Clinical interventions in aging

Human-verified similar examples from authoritative sources

Similar Expressions

56 human-written examples

All last observed dates of active work history before December 31 , 1997 for those still alive were considered terminations of active employment.

Epidemiology

Ten workers lost to follow-up were considered to be alive, but person-years of observation were truncated on the date each of these workers was last observed alive (date of termination, or last date known to be alive in earlier vital status follow-up).

Environmental Health Perspectives

The last observation date was August 31 , 2005

BMC Cancer

Survival time was defined from the date of HRCT to death or last observation date.

BMJ Open

Follow-up started on the day of diagnosis and concluded on the date the patient was last observed or the date of death.

BMC Cancer

Those with December 31 , 1997 as their last observed active work date were considered administratively censored at that time.

Epidemiology

For individuals lost to follow up, the end date was the date individuals were last observed, and for sheep that were confirmed alive at the end of the study period, this date was February 1 , 2007

BMC Ecology

Expert writing Tips

Best practice

When using "last observed date" in research papers, clearly define what constitutes an "observation" in your context to avoid ambiguity.

Common error

Avoid using "last observed date" when you actually mean "last contact date." The former implies a direct observation, while the latter suggests the final instance of communication or interaction.

Linguistic Context

The phrase "last observed date" functions primarily as a noun phrase acting as an adverbial modifier specifying a time point. As Ludwig AI indicates, it is usable and often found in scientific, medical, or data reporting contexts. The examples provided by Ludwig support this function, as they're predominantly from scientific journals.

Expression frequency: Common

Frequent in

Science

80%

News & Media

10%

Formal & Business

5%

Less common in

Wiki

3%

Encyclopedias

1%

Reference

1%

Ludwig's WRAP-UP

In summary, "last observed date" is a grammatically correct and commonly used phrase, particularly in scientific and medical fields. According to Ludwig AI, it accurately specifies the most recent date of an observation, crucial for studies involving survival analysis or longitudinal data. While alternatives like "date of last observation" or "most recent observation date" exist, the phrase is generally preferred for its conciseness and clarity. Remember to use it when denoting a direct observation rather than a mere contact and carefully define the meaning of "observation" within your context. Examples from Ludwig highlight the phrase's consistent application in academic and research settings.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

most recent observation date

Replaces "last" with "most recent" for clarity.

date of last observation

Reorders the words for a slightly more formal tone.

latest recorded date

Emphasizes the recording aspect of the observation.

final date of monitoring

Substitutes "observed" with "monitoring" and "last" with "final" for a slightly different emphasis.

last known date

Highlights the final confirmed date of something.

terminal observation date

Emphasizes the end point of the observation.

date of last contact

Replaces "observed" with "contact", implying the end of communication.

end of follow-up date

Indicates the cessation of a follow-up period.

cutoff date for observation

Indicates a specific date after which observations were not considered.

date of study completion

Implies that the observation period concluded with the study's end.

FAQs

How is "last observed date" typically used in scientific studies?

In scientific studies, "last observed date" is commonly used in survival analysis or longitudinal studies to indicate the final date a participant was known to be alive or under observation. This is important for handling censored data.

What's the difference between "last observed date" and "last follow-up date"?

"Last observed date" refers to the most recent date any observation was made, whereas "last follow-up date" specifically refers to the final date a subject was actively monitored or checked on within a study or clinical setting.

When should I use "date of last contact" instead of "last observed date"?

Use "date of last contact" when you are referring to the final date of communication with a subject, rather than a date when they were directly observed. For example, in a phone survey, you'd use "date of last contact".

Can I use "most recent observation date" interchangeably with "last observed date"?

Yes, "most recent observation date" is a suitable alternative to "last observed date" and carries the same meaning, though "last observed date" is slightly more concise.