Ex62 Answers 62-Time Study Observed Time In Minutes Activity

Ex62 Answersex 62time Studyobserved Time In Minutesactivityperform

Ex6.2 Answers EX 6.2 TIME STUDY Observed time (in minutes) Activity Performance Rating Observed time (OT) Normal Time (NT) Standard Time (ST) Registration 1. Co-payment 0. Wait for nurse 1. Vital signs 0. Wait for exam room 1. Placement to exam room 0. Wait for physician 1. Examination 1. Test order entry 1. Referral requests 1. Follow-up appt. Sched. 1..00 0.00 0.00 a. Job-OT b. Job-NT c. Job-ST d. 0.00 EX6.5 Answers EX6.5: a- Calculate the % of Idle Time EX6.5: b- Approximately how many observations to within 4%, 95% confidence?

Paper For Above instruction

Introduction

Time studies are fundamental tools in industrial engineering and workflow analysis, used extensively to improve efficiency and productivity in healthcare, manufacturing, and service industries. The core purpose of a time study is to determine the standard time required for a specific activity by observing and recording the time taken for tasks under normal working conditions. These measurements not only facilitate process improvements but also establish benchmarks for fair labor standards and compensation. This paper discusses key concepts related to time study analysis, including observed time, normal time, standard time, and idle time. Furthermore, it delves into calculations such as the percentage of idle time and the estimation of the number of observations needed to reach specific confidence levels in statistical analysis.

Understanding Time Study Components

The observed time (OT) is the actual time recorded during a task, which incorporates worker performance variations. Adjustments are necessary to reflect standard performance levels; thus, normal time (NT) is calculated by multiplying OT by a performance rating factor. The normal time represents the time it would take a worker operating at a standard pace. Standard time (ST) further incorporates allowances for fatigue, delays, and other contingencies, providing a realistic measure of task duration.

In the provided scenario, activities such as co-payment, waiting for a nurse, taking vital signs, and waiting for exam rooms are observed. These activities are typical in healthcare settings, contributing to overall process efficiency but often involving idle periods due to scheduling or resource availability.

Calculating Normal and Standard Times

The calculation of normal time involves multiplying observed time by the performance rating. For instance, if the observed time for a task is 1 minute with a performance rating of 1.0 (indicating normal performance), then the normal time equals 1 minute. If performance ratings vary, adjustments are made accordingly.

Standard time is obtained by adding allowances—usually a percentage of normal time—for factors such as fatigue and minor delays. For example, if allowances are 15%, then ST = NT × (1 + 0.15). Precise calculations depend on actual performance ratings and allowances specified, which are not explicitly provided here.

Idle Time and Its Significance

Idle time is the period during which workers are not actively engaged in value-adding activities. It can occur due to delays, waiting for resources, or process inefficiencies. Calculating the percentage of idle time helps managers identify bottlenecks and areas for process improvement.

Using the data, the percentage of idle time is computed as:

Idle Time % = [(Standard Time - Normal Time) / Standard Time] × 100

This formula assesses how much of the total standard time is unproductively spent waiting.

Sample Calculation of Idle Time Percentage

Assuming from the data:

- Normal Time (NT) = 1 minute

- Standard Time (ST) = 1.15 minutes (assuming 15% allowances)

Then,

Idle Time = ST - NT = 0.15 minutes

Percentage of Idle Time:

= (0.15 / 1.15) × 100 ≈ 13.04%

This indicates approximately 13% of the total time is idle, which could be reduced through workflow improvements.

Determining the Number of Observations

Accurate time study results require a sufficient number of observations to account for variability and ensure statistical confidence. To estimate the number of observations needed within ±4% of the true mean, given a 95% confidence level, the following formula based on statistical principles is used:

n = (Z × σ / E)^2

Where:

- n = number of observations

- Z = Z-value for 95% confidence (≈1.96)

- σ = standard deviation of observed times

- E = desired margin of error (4% of the mean)

In practice, the standard deviation (σ) is estimated from preliminary observations. Assuming minimal variability, approximate calculations suggest around 30-40 observations are necessary to achieve the desired confidence and precision.

It is important to note that increasing the number of observations reduces the margin of error, enhancing the reliability of the time study results. This ensures that process improvements or standardization efforts are based on robust data.

Conclusion

Time studies are vital tools in operational management, providing insights necessary for process optimization and efficiency enhancement. Correctly calculating observed, normal, and standard times allows organizations to set realistic performance benchmarks. Understanding and minimizing idle time directly contribute to reducing waste and improving productivity. The statistical determination of the required number of observations ensures the validity of time study conclusions, supporting informed decision-making in process improvement initiatives. As healthcare and other service industries continue to evolve, the application of rigorous time study methods remains essential for delivering high-quality, efficient services.

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