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LSU 20061 Nursing Mathematics: What Skills Do Nursing Students Bring to Drug Calculations? Roslyn Gillies Learning Skills Unit Student Support Services University of Western Sydney

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LSU 20062 A bit about where I come from

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LSU 20063

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4 what I do

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LSU 20065 and where I do it

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LSU 20066 UWS Sydney, NSW, Australia

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LSU 20067 A bit about UWS Six campuses covering entire west of Sydney 36 000 students 32 000 undergrads Larger campuses: Parramatta & Penrith Smaller: Hawkesbury & Blacktown Motto: Bringing knowledge to life Emphasis on practical courses, providing educational opportunities for students in the region

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LSU 20068 How does Nursing Mathematics fit with Ethnomathematics? Several definitions of ethnomathematics the study of mathematics which takes into consideration the culture in which mathematics arises (University of Idaho website) the mathematical practices of identifiable cultural groups (Ubiratan DAmbrosio first used in late 1960s)

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LSU 20069 Human activities which require some form of mathematics Architecture - construction Weaving textiles and baskets Sewing turning cloth/skins into clothing or shoes that fit Agriculture calendars to mark seasons, planning for quantity and storage, layout of gardens and fields Kinship relations Ornamentation tilings and beadwork Spiritual and religious practices (uidaho.edu website) and Nursing dosage calculations!

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LSU 200610 Mathematical skills nurses require Computational skills fractions, decimals, percentages, ratio, measurement, conversion between units Conceptual Skills- ability to: set up the problem for calculation apply an appropriate solution method

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LSU 200611 The culture and tradition of teaching drug calculation Early 1980s Florence Nightingales hospital-trained apprentice system was replaced by higher education training Occurred in countries such as: UK Canada USA Australia New Zealand

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LSU 200612 Impacts of this change Big bang curriculum revolution rather than incremental change Emphasis on intellectual and higher- level thinking skills, problem solving Mastery of basic principles rather than facts Less time in clinical practice situation

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LSU 200613 Other factors affecting drug calculation instruction Increasing student diversity Multidisciplinary nature of nursing maths (maths applied in a nursing context) Medication calculation frequently a stressful task performed on the ward No clear policy on whose responsibility it is to develop and maintain nurses drug calculation competence Little agreement on teaching methods

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LSU 200614 Other factors (cont.) Assumption that maths skills taught in the abstract will be successfully transferred to nursing context Some nursing educators admit to poor maths skills and difficulty in teaching drug calculations Limited opportunities for students to practice drug calculation skills Reliance on formula methods that do not always result in students retaining skills

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LSU 200615 The tradition of using formula methods for drug calculation Widespread use of formula methods Examples of formulae taught: Volume required to deliver a given mass: (Gatford & Phillips, 2002, p. 44)

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LSU 200616 Another formula taught Drip rate for Intravenous Infusion: (Hext & Mayner, 2003, p. 80)

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LSU 200617 Why are formulae taught? to bypass the need to appropriate or understand any mathematical structure and to impose consistency on what were seen to be dangerous variations in strategy (Hoyles et al., 2001, p. 13)

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LSU 200618 The dilemma Advantages of formula methods Standardised methods: one-size- fits-all Easy to apply Plug in the numbers and turn the handle to get the answer Dont need to think too much

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LSU 200619 Disadvantages of formula methods Little use of students existing problem- solving skills Encourage belief that drug calculation is a separate branch of mathematics Do little to encourage students to think through the problem and understand the calculation method Do little to encourage estimation and checking strategies to ensure calculated dosage is reasonable

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LSU 200620 What the literature says Some students find formulae difficult to use correctly Formulae may be a cause of conceptual errors Formula methods are frequently ineffective and result in: poor skill development poor retention of skills

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LSU 200621 What the literature says (cont.) In workplace situations nurses make little use of formulae learnt Instead, nurses use a variety of correct proportional reasoning methods that preserve the meaning of the problem situation (Hoyles et al., 2001)

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LSU 200622 The study Subjects: 35 recently enrolled first year B Nursing students at UTS Instruments: Test 10 calculations (see OHT) set in everyday contexts designed to parallel typical drug calculation problems Questionnaire demographic data

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LSU 200623 Problem types simulated in test Calculate: Number of tablets to deliver a given mass Volume required to administer a given mass, either: orally by injection Intravenous medications: drip rate (drops per minute) time to run the infusion

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LSU 200624 Some of the questions PRT item 4. A 12.5 kilogram bag of flour lasts a cook 5 days. How many days will 45 kilograms of flour last the cook? Parallel DCT item 4. On hand is Benadryl 12.5 mg per 5 mL. How many millilitres will you give if Benadryl 45 mg is ordered?

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LSU 200625 PRT item 5. An automatic drip feeder installed in an aviary is to deliver 600 millilitres of water to the birds every 10 hours. If the feeder delivers 60 drops per millilitre, how many drops are delivered each minute? Parallel DCT item 5. An intravenous drip is to deliver 600 mL of normal saline over 10 hours. If the giving set delivers 60 drops per mL, what is the drip rate in drops per minute?

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LSU 200626 PRT item 7. A dripping kitchen tap loses 1 litre of water over 8 hours. It is established that 15 drops of water is equivalent to 1 millilitre. Calculate in drops per minute the rate at which the tap is losing water. Parallel DCT item 7. A patient is ordered 1 litre of normal saline over 8 hours. The intravenous giving set delivers 15 drops per mL. Calculate the drip rate in drops per minute?

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LSU 200627 PRT item 10. A car travelling on a country road is losing water from the radiator at the rate of 25 drops per minute. The driver uses his last 600 millilitres of water to top up the radiator. How long will it take for this amount to leak out if 20 drops of water is equivalent to 1 millilitre? Parallel DCT item 10. An intravenous giving set is delivering an infusion at the rate of 25 drops per minute. The patient is to have 600 mL of Hartmanns. How long will the infusion take if the giving set delivers 20 drops per mL??

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LSU 200628 Research questions Before being exposed to drug calculation instruction of special formulae: How well do students perform on tasks similar to drug calculations? How successful are students in applying appropriate problem-solving methods to set up the problem for calculation? What are the native methods used by students to solve such problems?

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LSU 200629 Scoring two methods Method 1 right/wrong test mark out of 10 Method 2 score/3 for each item test mark out of 30 1 mark: some progress 2 marks: correct method used 3 marks correct method and correct answer

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LSU 200630 Student profile Female: 94% Ages: 17-48 mean 25.6 (sd 7.7) Mathematics backgrounds: NSW HSC-level mathematics: 78% Year 10 (junior high) maths or less: 20% Maths studied after leaving school: 9% NESB Language background: 12%

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LSU 200631 Mean score Method 1 (score/10) Mean score: 3.65 (sd: 2.25) Method 2 (score/30) Mean score: 15.17 (sd: 7.57)

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LSU 200632 Pass requirement: 80% correct Method 1: (score 8/10) Pass:11% of students Fail:89% Method 2: (score 24/30) Pass:17% Fail:83%

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LSU 200633 Pass requirement: 100% correct Methods 1 & 2: (Score: 10/10 or 30/30) Pass:0% Fail:100%

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LSU 200634 Deficits in students skills Inability to set up problem for calculation (Blais & Bath, 1992; Rutherford, 1996) Computational errors (Gillies, 1994; Gillham & Chu, 1995) Errors in metric conversions (Rodger & Jones, 2000)

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LSU 200635 Some of the problem-solving methods students used Division operations Unitary method and adaptations Fraction of a quantity Proportion (formal set up) Ratio Proportional reasoning Rewrite rate in equivalent form

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LSU 200636 No of items where correct method applied

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LSU 200637 Ability to apply correct method On average, another 1.4 Qs per student where correct method used For 26% of students, a further 3-4 Qs where correct method used For 40% of students, at least 2 additional Qs where correct method used

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LSU 200638 Items of particular interest Those with greatest difference between % of students obtaining correct answer and % using correct methodItems 4, 5, 7, 10 ie many more students can apply a correct method than can get the correct answer These include all three IV infusion problems traditionally most difficult Qs For these items, high incidence of causes, other than conceptual difficulties, that prevent success viz computational difficulties

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LSU 200639 Item 5 Melikas working

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LSU 200640 Item 5 Nicolas working

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LSU 200641 Item 5 - Summary Key to success: Being able to convert: ml to drops hours to minutes Being able to express stated drip rate in appropriate equivalent forms

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LSU 200642 Item 7 Cates working

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LSU 200643 Item 7 Alisons working

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LSU 200644 Item 7 Melikas working

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LSU 200645 Item 7 Karens working

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LSU 200646 Item 7 - Summary Simplest process: Change ml to drops early Leave conversion of hours to mins until the end (otherwise large numbers result) Also valuable was the ability to express division in fraction form and cancel down (avoids long division)

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LSU 200647 Item 10 Karens working

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LSU 200648 Item 10 Melikas working

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LSU 200649 Item 10 - Summary Both students used same method Both had difficulty in arithmetic processes: Karen gained a zero is division (2-step process) Melika lost a zero in same division (long division)

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LSU 200650 What analysis of students working suggests Difficulties with IV problems are not always because of conceptual difficulties Many students able to set up problem and apply appropriate method Having applied an appropriate method, poor conceptual skills may prevent progress to correct answer

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LSU 200651 Conclusions On average, students able to apply correct method to half of the 10 items even before any drug calculation instruction Many students fairly well equipped to deal with even the most difficult drug calculation problems (IV problems) Methods students use involve multiple steps that preserve meaning of problem (Hoyles et al., 2001) When correct method applied, incorrect answers caused by poor arithmetic skills (Gillham & Chu, 1995; Cartwright, 1996)

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LSU 200652 Recommendations for nursing educators Need to reassess the appropriateness of focus on teacher-taught formulae for drug calculations Avoid killing off students existing problem-solving skills Avoid fostering the belief that drug calculation is a separate and unrelated branch of maths Encourage students who prefer to use native methods and assist them in refining those methods

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LSU 200653 Recommendations cont. If formulae taught, ensure development of understanding: Unravel the multiple steps embodied in the formula Stress these steps may be performed separately Encourage students to think flexibly and apply a range of problem-solving methods leads to mathematically powerful students (Schoenfeld, 1992) Further research needed in areas such as: the conceptual skills of nursing students students native problem-solving methods and how they might apply them to drug calculation