Schedule Health Assessment

Schedule Health Assessment

The Schedule Health report is a project metric analysis tool that provides detailed insight into schedule quality and key project performance metrics. Understanding the content and quality of a schedule is often difficult unless you develop the schedule yourself. You can use the schedule health report to help you assess a schedule’s integrity and credibility.

The Safran Schedule Health report assists you in evaluating the quality of the schedule, providing critical metrics such as the number of tasks missing logic, total, incomplete activities, activities with constraints, activities with long durations, urgent tasks, float, link type information, and more.

Your schedule, and your baseline in particular, reflect the agreed-to implementation of your plan at the beginning of the project or after a significant re-planning during the lifecycle of the project. It provides the basis required for sound schedule control and sets the benchmark against which the project's progress is measured.

Suppose the baseline—or, more generally, the schedule or plan at any stage—is crucial to project success. In that case, it makes sense to do everything necessary to ensure it’s accuracy according to standards and recommendations and maintained correctly.

The Schedule Health report provides summary listings together with credibility and performance indicators. For the execution phase of your project, the Schedule Health report provides Baseline Execution Indices, Performance Indices, and Completion Ratio. The Schedule Health report supports both the '14-point schedule' metrics and the 'Tripwire' metrics.

One significant benefit of running a schedule health report and performing a schedule health assessment is that more people are likely to engage in the work associated with establishing a credible schedule.

Does Your Schedule Pass the Test?

The objective of any schedule assessment is to provide a set of tools and indicators for determining your schedule’s completeness and practicality, whether it's your baseline schedule or any later update. You will probably agree that if your schedule is essential to project success and to sound project schedule and control, then it makes sense to do everything you can to ensure it is accurate and maintained correctly. Because if it’s not, then your schedule:

• It may not reflect the total scope of work.
• It may not provide sound project logic.
• It may reflect an inaccurate or incomplete status.
• It may reflect an inaccurate model of planned implementation.
• It may not provide Critical Path identification or float for all activities or milestones.
• It may provide an incorrect basis for resource planning.
• It may not provide for ‘What-If’ analysis.

A schedule assessment is essential because the schedule may not reflect an accurate and truthful picture. The plan and status may be inaccurate, or the scheduling process may be flawed.

Credibility Indicators

The key components of your schedule are a critical path method (CPM) tool, sound project logic, work calendars, and resource requirements. Sound project logic should provide the basis of all project schedule data. It is a model that reflects the planned project implementation and sequencing using activities and milestones, interdependencies, durations, and date constraints.

Scope of Work

Your schedule should reflect all activities, the total scope of work, and all WBS elements. If not, it can indicate that the project, the schedule, or both are poorly defined. Later in the project, it can also indicate a lag in implementing changes. An inaccurate model of the planned work provides an incorrect basis for resource planning. Many modifications to the scope of work (count and work) may also indicate that the project is poorly defined.

Missing Logic - Dangling Activities

All activities and milestones should have interdependencies assigned. Exceptions are project start and completion and external deliveries. Missing logic should be identified as it may impact your schedule.

• Activities with no successors may slip with no resulting visible impacts.
• Activities with no predecessors may incorrectly reflect start dates that are too early or start dates that are not realistic.
• Hampers accurate critical path identification.
• Hampers reliable “what-if” analysis.
• Hampers reliable alternative analysis.
• Hampers credible free float and total float calculations.

Relationship Types

Project logic should be predominantly Finish-to-Start (FS) relationships. The FS relationship type (once the predecessor is finished, the successor can start) provides a logical path through the project. The Start-to-Finish relationship is non-intuitive (the successor cannot complete until its predecessor is started) and should only be used rarely.

Delays

The size and frequency of delays should be minimized. Delays (positive or negative) can manipulate float or constrain the schedule. The critical path, project duration, total and free float, and schedule analysis can be affected negatively using delays.

Number of Constraint Dates

Ideally, minimal use of date constraints is strongly recommended. Constraints prohibit accurate calculations for total project critical path identification and analysis, wrong free float and total float values, and potentially incorrect activity start and finish dates. Using hard constraints will prevent activities from being moved by their dependencies, preventing the schedule from being logic-driven.

• Start No Earlier Than
• Finish No Earlier Than
• Start No Later Than
• Finish No Later Than
• Must Start On
• Must Finish On
• As Late As Possible

High Float

An activity with high float may result from wrong or missing logic. If the number of activities with high float is excessive, this may indicate that the project is unstable or not logic-driven. On the other hand, if the logic is sound, a path with a high float may suggest that extra work can be added to accelerate work, given that the resources to complete the work are available during this period.

Negative float

Activities with negative float should have an explanation and a corrective action plan. Ideally, there should not be any negative float in the schedule.

High Duration

The schedule should realistically reflect how long each activity would take to execute. These durations should be as short as possible. They should be manageable, meaning you can measure progress against it. Activities with long durations may be broken down into more discrete activities rather than one activity. This helps to make activities more manageable, which provides better insight into work and schedule.

Assigning Resources to All Activities

The schedule should reflect what resources are needed to complete the work. Resource requirements should align with availability to represent a feasible schedule.

Inaccurate and Improperly Scheduled Activities

You should avoid assigning actual start/finish dates later than the cut-off dates to activities scheduled to occur in the future. Another critical aspect is ensuring the cut-off date is current and not too far in the past to be meaningful. Out-of-date data is just another way of saying it is inaccurate. You should also watch out for sequence updates.

Maintaining the integrity of the schedule and its logic is not only necessary to reflect actual status, but is also required to foster confidence in the schedule.

Major Project Milestone Tracking

Slips in early key project milestones typically lead to slips in key milestones later in the project. Your project should contain end-to-end project logic, including your project milestones, and the activities and milestones should be sequenced in the order they take place. If slippage in early project milestones does not have a knock-on effect and impacts later crucial milestones, it could be caused by incomplete logic.

Testing Your Schedule

What test or evaluation work should you do besides running a schedule health assessment report? Safran's Schedule Health Report helps you collect and summarize various indicators and items of information concerning your schedule. In addition, you should carefully examine your schedule using Safran reports such as the Barchart Editor, The Histogram/S-Curve reports, and the Performance charts. The Barchart Editor should be used to check the critical path—the longest duration path through the sequenced list of activities.

You can use the Safran Project histograms to evaluate manpower requirements for the total project by phase, area, section, block, floor, or any group or sub-group of interest. You can use S-curves and spread curves to evaluate planned productivity. Spread curves can be used to assess a project's phasing or evaluate, for example, the planned productivity by trade in different modules, sections, floors, and more. Use the Safran reporting facility to ensure all WBS have resources, work, or costs assigned to them.

Schedule Health Report Indicators

The schedule health report uses metrics that have been found to meet the criteria for the Schedule Health Assessment. It is a framework for improving your project schedule. You can run the schedule health report as part of your self-analysis before the schedule is discussed and critiqued by any other project stakeholder.

Several initiatives, papers, and discussions around improving CPM schedules have been seen over the last several years. Two are the DCMA's 14-point Assessment and the Tripwires on scheduling. The focus of these initiatives is on validating the structural integrity of your schedule.

The Safran Schedule Health report provides the necessary metrics and standard configurations for both the 14-point assessment and the tripwire initiatives.

In addition, you can also select and store a User defined configuration containing any number of the available schedule metrics.

Using the configuration panel, you can select from many indicators. The majority of the checks focus on the planning phase of your project. However, some checks (baseline execution index, CPI, SPI, TCPI, Hits, Invalid dates, etc.) focus on performance and status during execution. The following section reviews the different metrics, indicators, and checks.

Activity Count

Total Number - will display how many activities and milestones are part of the plan and, in addition, how many of these are critical (Float<=0).

Completed - will display how many activities and milestones are completed (Actual %=100).

Planned to complete - will display how many activities and milestones are scheduled to be finished.

Completion Ratio - is calculated based on the formula Completed/Planned to complete.

Hits - the number of activities and milestones finished before or on the baseline finish date.

Misses - is the number of activities and milestones that finished later than the baseline finish date.

Remaining/Incomplete - will display the number of activities and milestones that are not finished.

Logic Indicators

The logic checks provide the total number of dangling activities or activities that are missing logic. These checks also summarize the number of activities with targets, the total number of links and non-Finish-Start links, invalid future dates (actual dates in the future), and the number of links with positive and negative delays. Delays are used to delay or accelerate the sequence of activities and can be a risk. They are often used to adjust the CPM dates to fit a target delivery date, and when used to represent actual delay between two tasks, they may become difficult to manage.

A project with missing logic and usage of targets may not show the effect of delays in one area throughout your project schedule. This has implications, like an overly optimistic schedule. Project completion dates in a schedule are driven by two factors: activity duration and logic. The logic checks do not unmask wrong sequencing (you cannot build the walls before you lay the foundation) but focus on the summary of how structured the schedule is. A project schedule with missing logic may give you incorrect completion dates driven by the critical path analyses. Negative delays should be minimal.

By adding the link types check to your assessment, Safran also summarizes the statistics of links by type (Start-Start, Start-Finish, Finish-Start, and Finish-Finish). Use this indicator to validate different link types. Your project logic should be predominantly Finish-Start relationships (above 75%).

Constraints or targets are dates applied to an activity that override dates computed by your project logic. Extensive use of target dates may lock your schedule projects, as they go against the essence of CPM scheduling. There are instances where constraints or targets can address an open end within a schedule. Many users and schedulers use milestones to represent these start or finish points.

Activity Duration and Float Statistics

Schedule checks for high duration, high float, and negative float allow schedule improvements. The high float may indicate that logic relationships are potentially incorrect. However, high float can suggest that the amount of work in a path is small. If so, can you use this float to add work, accelerating the schedule without impacting the critical path? The amount of negative float or activities with low float indicates a tight and critical schedule.

The duration profile data indicates the level of detail in your schedule. Activity durations should be discrete and measurable. The Critical Path Length Index (CPLI) gauges the reality of completing the project or contract on time. It would be best to verify that the critical path makes sense and that enough of the schedule metrics have indicated that you have a “believable” and sound CPM schedule.

The critical path index computes as follows:

CPLI = (Critical Path length + Total Float)/Critical Path Length

The target value is 1.00. A value greater than 1.00 is favorable.

Knowing that companies define projects and schedules differently when using the available project length, we have implemented four options to set the default finish for this calculation.

Execution Phase Indicators

Execution indexes reveal information on how well you are performing according to plan. The Schedule and Cost performance indexes and the To Complete performance indexes should be familiar to most planners. The Baseline Execution index computes the number of activities started/finished on or before its baseline start/finish at the latest cut-off. Why do you need both baseline indexes? You may be a good starter but are so good at finishing your work. Looking at both indicators may give you an insight into different possible problems.

During the execution phase, you can also compute remaining project time, display the current start and finish, and count the number of activities and milestones progressed and completed out of sequence, completed, remaining/planned, and the number of activities and milestones hit and missed activities. A missed activity is an activity that should already be completed and has a missing actual finish or an actual finish date after the baseline finish date.

Contract Change Volume

Three indicators specifically address the changes to schedule and scope of work. The first is the number of activities added to your schedule since the last baseline, i.e., activities without baseline dates.

Directly related to the contract scope of works are the revision indicators. The Contract Modification Indicators (CMOD) show the scope added to your schedule since the first (original) baseline was set. A high CMOD value indicates that the scope of work is not well defined or well defined at the time of project start. The Baseline Revision Indicator (BREV) will specify if this is true. You should examine the situation closely if a new baseline has been agreed upon and the scope changes.