
Calculate with Confidence
- 9th Edition - January 20, 2026
- Latest edition
- Author: Deborah C. Morris
- Language: English
- Paperback ISBN:9 7 8 - 0 - 4 4 3 - 1 2 7 3 2 - 8
- eBook ISBN:9 7 8 - 0 - 4 4 3 - 1 2 7 3 3 - 5
Learn how to make accurate drug calculations and administer medications safely! Calculate with Confidence, 8th Edition, makes it easy to understand the three major methods of do… Read more
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Learn how to make accurate drug calculations and administer medications safely! Calculate with Confidence, 8th Edition, makes it easy to understand the three major methods of dosage calculation — ratio and proportion, formula, and dimensional analysis. Clear, step-by-step instructions guide you through accurate calculation and safe administration of drug dosages. Thousands of practice problems ensure that you gain proficiency, patient safety is prioritized, and an emphasis on clinical judgment helps you prevent medication errors. Next-Generation NCLEX® (NGN) Exam–style case studies help you improve clinical judgment skills. With this popular text from trusted educator Deborah C. Morris, you will learn to calculate drug dosages and administer medications with confidence and a high degree of patient safety!
- More than 2,000 practice problems include a pre-test and a comprehensive post-test review.
- Three-part approach to evaluating basic math skills includes a pre-test, comprehensive unit, and review tests.
- Medication Administration chapter covers medication safety, a discussion of client rights, the basic six rights of medication administration, and routes of medication administration.
- Chapter review problems (with answer key) test all major topics presented in the chapter and help you assess your understanding of chapter content.
- Safety Alert boxes highlight issues that may lead to medication errors and empower you to identify actions that must be taken to avoid calculation errors.
- Tips for Clinical Practice boxes call attention to information critical to math calculation and patient safety and equip you with the tools needed to follow best practices in patient care.
- Rule boxes present important instructions essential to math calculations and familiarize you with information needed to accurately solve drug calculation problems.
- Clinical Reasoning Scenarios discuss safety issues related to medication administration.
- Points to Remember feature provides bulleted key points from the chapter.
Undergraduate nursing students
Unit One: Math Review
Pre-Test
1. Fractions
2. Decimals
3. Ratio and Proportion
4. Percentages
Post-Test
Unit Two: Systems of Measurement
5. Metric System
6. Apothecary and Household Systems and Additional Measures Used in Medication Administration
7. Converting Within and Between Systems
8. Additional Conversions Useful in the Health Care Setting
Unit Three: Methods of Administration and Calculation
9. Medication Administration
10. Understanding and Interpreting Medication Orders
11. Medication Administration Records and Medication Distribution Systems
12. Reading Medication Labels
13. Dosage Calculation Using the Ratio and Proportion Method
14. Dosage Calculation Using the Formula Method
15. Dosage Calculation Using the Dimensional Analysis Method
Unit Four: Oral and Parenteral Dosage Forms and Insulin
16. Oral Medications
17. Parenteral Medications
18. Reconstitution of Solutions
19. Insulin
Unit Five: Intravenous, Heparin, and Critical Care Calculations and Pediatric and Adult Calculations Based on Weight
20: Intravenous Solutions and Equipment
21. Basic Intravenous Calculations
22. Heparin Calculations
23. Critical Care Calculations
24. Pediatric and Adult Dosage Calculation Based on Weight
Comprehensive Post-Test
References
Appendices
A: Apothecary System
B: FDA and ISMP Lists of Look-Alike Drug Names with Recommended Tall Man Letters
C: TJC’s “Do Not Use” List of Abbreviations
D: ISMP’s List of Error-Prone Abbreviations, Symbols, and Dose Designations
E: ISMP List of High-Alert Medications in Acute Care Settings
F: ISMP List of High-Alert Medications in Community/Ambulatory Healthcare
Index
Drug Label Index
Pre-Test
1. Fractions
2. Decimals
3. Ratio and Proportion
4. Percentages
Post-Test
Unit Two: Systems of Measurement
5. Metric System
6. Apothecary and Household Systems and Additional Measures Used in Medication Administration
7. Converting Within and Between Systems
8. Additional Conversions Useful in the Health Care Setting
Unit Three: Methods of Administration and Calculation
9. Medication Administration
10. Understanding and Interpreting Medication Orders
11. Medication Administration Records and Medication Distribution Systems
12. Reading Medication Labels
13. Dosage Calculation Using the Ratio and Proportion Method
14. Dosage Calculation Using the Formula Method
15. Dosage Calculation Using the Dimensional Analysis Method
Unit Four: Oral and Parenteral Dosage Forms and Insulin
16. Oral Medications
17. Parenteral Medications
18. Reconstitution of Solutions
19. Insulin
Unit Five: Intravenous, Heparin, and Critical Care Calculations and Pediatric and Adult Calculations Based on Weight
20: Intravenous Solutions and Equipment
21. Basic Intravenous Calculations
22. Heparin Calculations
23. Critical Care Calculations
24. Pediatric and Adult Dosage Calculation Based on Weight
Comprehensive Post-Test
References
Appendices
A: Apothecary System
B: FDA and ISMP Lists of Look-Alike Drug Names with Recommended Tall Man Letters
C: TJC’s “Do Not Use” List of Abbreviations
D: ISMP’s List of Error-Prone Abbreviations, Symbols, and Dose Designations
E: ISMP List of High-Alert Medications in Acute Care Settings
F: ISMP List of High-Alert Medications in Community/Ambulatory Healthcare
Index
Drug Label Index
- Edition: 9
- Latest edition
- Published: January 20, 2026
- Language: English
DM
Deborah C. Morris
Affiliations and expertise
Professor of Nursing, Department of Nursing and Allied Health Sciences, Bronx Community College, Bronx, NY