HR research and reference notes
Research for better HR decisions
Research, original sources, and practical guidance for decisions about hiring, managing employees, pay, and compliance.
Find the right resource
Choose where to start
Read the evidence behind an HR decision, calculate its financial impact, find a tool you can use, or discuss your options with a senior HR practitioner.
Review the evidence
Find the key findings, who they apply to, and the original sources.
Read the standard →Calculate costs
Use free calculators to estimate turnover, vacancy, and other workforce costs.
See the free calculators →Use an operating tool
Find editable templates, kits, and workbooks for hiring, managing employees, and day-to-day HR work.
See the operating tools →Work with a practitioner
Discuss your assessment results in a Results Debrief, or get help adapting a purchased kit in a Setup Session.
See the sessions →Featured reference notes
Start with a common HR question
Research and practical guidance on compliance, staffing, costs, and managing employees.
The cost of caregiver turnover in home care
Explore caregiver replacement costs and why the first 90 days matter.
Reviewed 6 July 2026 ComplianceFMLA eligibility: four requirements to check
See how employer coverage, tenure, hours worked, and worksite size determine FMLA eligibility.
Source checked 13 October 2026. ComplianceUnderstanding the four-fifths rule
Learn how the 80% selection-rate comparison identifies outcomes for closer review.
Source checked 13 October 2026.Build or buy
Build or buy an HR tool
Compare the time and cost of building an HR tool with buying one.
All reference notes
Find a reference note
Search by topic or filter by subject and source type.
WARN Act requirements and state notice laws
Learn how employment losses and the 90-day period affect WARN coverage.
Source reviewed 13 October 2026 → ComplianceUnderstanding the four-fifths rule
Use the four-fifths rule to identify selection outcomes for closer review.
Source reviewed 13 October 2026 → CompliancePWFA and PUMP Act requirements for employers
Check the 15-employee accommodation threshold and pumping space requirements for one year.
Source reviewed 13 October 2026 → ComplianceWARN Act: the 60-day notice requirement
Check the 60-calendar-day notice requirement for covered employers with 100 or more employees.
Source reviewed 13 October 2026 → CompliancePlanning and documenting a reduction in force
Build a business case, establish selection criteria, review employee impact, and prepare the necessary documentation and waivers.
Source reviewed 13 October 2026 → ComplianceAt-will employment and employee protections under Section 7
Understand at-will employment in 49 states and federal protections for concerted activity.
Source reviewed 13 October 2026 → ComplianceFMLA eligibility: four requirements to check
Check the four requirements used to determine federal FMLA eligibility.
Source reviewed 13 October 2026 → ComplianceFederal HR record retention requirements
Compare federal record retention periods and identify the requirements that apply.
Source reviewed 13 October 2026 → ComplianceThe 16 March 2026 Form I-9 enforcement changes
Understand the 16 March 2026 change to Form I-9 enforcement procedures.
Source reviewed 13 October 2026 → ComplianceAttendance-point policies and protected leave
See how protected leave affects attendance-point policies.
Source reviewed 13 October 2026 → ComplianceSeverance agreements for employees age 40 and older
Review OWBPA waiver requirements, including the 21-day consideration period, 45-day period for group programs, and seven-day revocation period.
Source reviewed 13 October 2026 → ComplianceSix federal labor law posting requirements
Find federal posting requirements, including those that apply at 15 and 50 employees.
Source reviewed 13 October 2026 → ComplianceTraining ROI and certification tracking
Explore five training evaluation levels and ways to document certification requirements.
Source reviewed 13 October 2026 → GlobalThe EU AI Act in employment
Understand high-risk employment requirements and the implementation timeline, including the 2 December 2027 milestone.
Source reviewed 13 October 2026 → GlobalThe EU Pay Transparency Directive
Check the 7 June 2026 transposition deadline and country-specific requirements.
Source reviewed 13 October 2026 → GlobalMexico's transition to a 40-hour workweek
Explore Mexico's planned transition to a 40-hour workweek by 2030.
Source reviewed 13 October 2026 → GlobalOntario’s 2026 job posting rules
Understand Ontario's pay disclosure requirements and the $50,000 range provision.
Source reviewed 13 October 2026 → IndustryThe cost of caregiver turnover in home care
See how caregiver replacement costs of $2,600 to $5,000 affect home care businesses and why early departures matter.
Source reviewed 6 July 2026 → IndustryThe cost of a technician vacancy in home services
Estimate the daily revenue impact of an unstaffed truck, from $2,000 to $7,800.
Source reviewed 6 July 2026 → IndustryThe role of a dental practice manager
Review a dental practice manager's responsibilities for staffing, employee relations, and performance.
Source reviewed 13 October 2026 → IndustryThe role of a clinic manager
See how clinic managers support staffing decisions and employee retention.
Source reviewed 13 October 2026 → IndustryThe construction foreman's role in crew performance
Learn how construction foremen contribute to crew stability and retention.
Source reviewed 13 October 2026 → IndustryThe warehouse supervisor's role in team performance
Explore the warehouse supervisor's role in team stability and retention.
Source reviewed 13 October 2026 → IndustryEmployee turnover costs in the trades
Estimate replacement costs using a range of half to twice annual pay.
Source reviewed 13 October 2026 → IndustryThe cost of employee turnover in a dental practice
Explore the estimated $8,000 to $12,000 cost of replacing a dental hygienist.
Source reviewed 13 October 2026 → IndustryWhat turnover costs in a plant
Estimate manufacturing employee replacement costs using a $10,000 to $40,000 range.
Source reviewed 13 October 2026 → MetricsContingent labor costs: markup, employment expenses, and conversion
Compare contractor markup, employment costs, and conversion expenses.
Source reviewed 13 October 2026 → MetricsHow to calculate cost per hire
Calculate cost per hire using recruiting expenses, internal time, and total hires.
Source reviewed 13 October 2026 → MetricsThe cost of employee turnover
Replacing an employee can cost half to twice their annual salary.
Source reviewed 13 October 2026 → MetricsHow to estimate the cost of absenteeism
Estimate absence costs using wages, coverage, and productivity assumptions, including the 1.6x daily wage benchmark.
Source reviewed 13 October 2026 → MetricsThe full cost of an employee beyond salary
See how payroll taxes, benefits, and overhead contribute to total costs of 1.25 to 1.4 times salary.
Source reviewed 13 October 2026 → MetricsHR staffing ratios and span of control
Compare HR staffing levels with SHRM's 2025 median of 1.98 HR employees per 100 workers.
Source reviewed 13 October 2026 → PayState pay transparency posting laws: which states require a pay range in the job posting
Compare the 14 states and Washington, DC, that require a pay range in job postings.
Source reviewed 13 October 2026 → PayUsing compa-ratio and range penetration in pay decisions
Understand how compa-ratio and range penetration support salary decisions.
Source reviewed 24 June 2026 → PayDo employers have to pay for training time and travel time?
For hourly employees, federal law usually counts required training as paid working time. Travel depends on the kind of trip.
Source reviewed 25 October 2026 → PayFinal paycheck laws by state
No federal law requires an immediate final paycheck. The deadline comes from the state where the employee works.
Source reviewed 25 October 2026 → PayThe 2026 federal salary threshold for FLSA exemptions
The 2026 federal salary threshold for most executive, administrative, and professional exemptions is $684 per week.
Source reviewed 13 October 2026 → TalentEmotional intelligence at work
Review research on the relationship between emotional intelligence and job performance.
Source reviewed 21 July 2026 → TalentPsychological safety at work
Understand Edmondson's framework and the relationship between psychological safety, high standards, and team performance.
Source reviewed 13 October 2026 → TalentConflict at work
See what research says about workplace conflict, including the approximately 4.3 hours per week reported in 2022.
Source reviewed 13 October 2026 → TalentThe Five-Factor Model and the IPIP-NEO-120
Learn about the Big Five personality traits and the public-domain IPIP-NEO-120 assessment.
Source reviewed 29 June 2026 → TalentSituational judgment and the maturity-stage read
Understand four maturity stages and how to interpret scenario-based results without a normative percentile.
Source reviewed 1 July 2026 → TalentCandidate ghosting
See how consistent communication improves the candidate experience.
Source reviewed 13 October 2026 → TalentDifficult conversations and the SBI framework
Use the Situation, Behavior, Impact framework to make feedback more specific.
Source reviewed 13 October 2026 → TalentManager capability and performance calibration
See how calibration helps managers apply performance ratings consistently.
Source reviewed 13 October 2026 → TalentNew-hire onboarding and the 30-60-90 ramp
Review SHRM's finding that nearly a third of new hires quit within six months, and plan a 30-60-90-day transition.
Source reviewed 9 October 2026 → TalentEmployee referral program ROI
Explore referral hiring benchmarks, including 7% of applicants and more than 30% of hires.
Source reviewed 24 June 2026 → TalentRetention and stay interviews
Use stay interviews to learn what encourages employees to stay.
Source reviewed 6 October 2026 →No reference notes match your search.
Try overtime, turnover, or another HR topic.