A systematic observation and recording of activities of one or more individuals at random interval is done in –
Work sampling

It is systematic observation and recording of activities of one or more individuals, carried out at predetermined or random intervals.
It provides quantitative measurement of various activities.
It helps in standardizing the methods of performing jobs and determining the manpower needs in any organization.

Input-out analysis

Input → All health service activities which consume resources (manpower, money, material and time).
Output → Useful outcomes (cases treated, lives saved).
Input-output analysis shows how much of each "input" is needed to produce a unit amount of each "output".

Systemic analysis

Systemic analysis is essentially finding the cost-effectiveness of the available alternatives.
Systems analysis
Network analysis
Work sampling
Input–Output analysis