Psychology of Work and Organizations, N. K. Semmer Norbert K. Semmer University of Bern Psychology of Work and Organizations 1 Geneva September 6, 2013

Psychology of Work and Organizations, N. K. Semmer

1

Norbert K. SemmerUniversity of Bern

Psychology of Work and Organizations

Human Error

GenevaSeptember 6, 2013

or

Why the real surprise is that so little goes wrong

Swisstransfusion 2013


4

Three aspects:

1. cognitive

2. motivational

3. social

Human Error


5

I.The cognitive aspect

Attention, Routine, Slips/Lapses


6

MistakesErroneous judgment

• Action is intended

• Immediate result is intended

• Consequences of action not intended

• Action consciously controlled

• Action not carried out as intended

• Immediate result not intended

• No, or only partial, conscious control

Slips / LapsesFalse execution of action

Error Types

Examples: • Diagnosis wrong• Dose wrongly calculated

Classic routine errors. Examples:• Tube not securely fastened

Administering drug that looks similar


7

Reduced attention is what makes routine efficient: It frees mental capacity!

Slips and Lapses: Routine actions

We especially revert to routine under stress when fatigued

Need less conscious attention Need less mental capacity Cannot be controlled easily Are automatically triggered by (seemingly) appropriate

situations – sometimes after a very long time!


8

To look more intensely means to see more But: Attention is selective

Attention:Typical misconceptons

Attention can be consciously controlled only partly (e.g., distraction!) only for a limited time (fatigue) True (uninterrupted) vigilance is possible only for

about 30 to 45 minutes

The often heard conclusion: „If he only had been more attentive“often misses the point

Check ergonomics (e.g., similar appearance of drugs) Check for fatigue (working time; breaks) Check for interruptions and distractions


11

Availability: what comes to mind easily Frequency: What we have seen / experienced often Vividness: What has impressed us

Representativity: Similarity in core characteristics

Influences on our judgment: Heuristics

Like routine: Heuristics make us efficient, and they often work well.

But they also contain risks

In many situations, we do not systematically gather and weight the evidence

Rather, we take “mental shortcuts“

Tropical illlness, symptoms similar to a flu Diagnosis „flu“ not improbable

Mistakes


12

Making jugdments

Processing informationaffected by what we expect

Making judgmentsaffected by heuristics

Search for confirming information(Confirmation Bias)

Information that does not fit often is• ignored

• explained away

Efficient

Mostly correct

Þ Make at least one „mental loop“:

Is there anythingthat runs counterto my conclusion?

That‘s where it gets dangerous

• misperceived


13

Confirmation Bias and medical diagnosis:an exmple from a simulator study

20 Groups à 3 MDs

> “Patient“ is handed over> Diagnosis: Pneumonia> Treated with penicillin> MD who hands over reports unsuccessful attempt to insert

a subclavian catheter

> “Patient“ ist allergic to penicillin> Correct diagnosis anaphylactic schock > Type of symptoms + unsuccessful insertion of catheter:> Suggest tension pneumothorax

> Lung sounds are objectively identical> In 10 of 20 Teams at least on MD «hears« a difference

> Correct diagnosis: 6 groups / with help: 8 / No: 6

Tschan, F., Semmer, N. K., Gurtner, A., Bizzari, L., Spychiger, M., Breuer, M., & Marsch, S. U. (2009). Explicit reasoning, confirmation bias, and illusory transactive memory: Predicting diagnostic accuracy in medical emergency driven teams in a simulator setting. Small Group Research, 40, 271-300.


16

Wir underestimate risks...

...if we have successfully dealt with them frequently

...if they are not vivid

Personal Risk-Estimationfrequently is lower than risk-estimation in general!

(Illusion olf invulnerabiity)

Estimation of Risk


-4

-3

-2

-1

0

1

2

23 13 28 1 30 22 3 14 32 16 19 33 10 17 24 29 5 31 20 12 7 2 11 9 21 4 6 8 18 27 26 25 15

realistisch

unterschätzt

Risk estimation for 33 activities in a coal minepositive = overstimated / negative = underestimated

After: Musahl, H.-P. (1997). Gefahrenkognition: Theoretische Annäherungen, empirische Befunde und Anwendungsbezüge zur subjektiven Gefahrenkenntnis (Perception of danger: Theoretical approaches, empirical findings, and application for subjective risk estimation). Heidelberg: Asanger. [Tab. 44; S. 276]

Diff

ere

nce

(sta

ndar

dize

d )

Activities

These four activities are involved in50.6%

of all accidents!

18

Most activities are estimated realistically

However:


19

Estimating risks: I versus others(glass production)

Coll. Myself Coll. Myself0

1

2

3

4

5

6

1.93

1.13

4.49

3.05

“What‘s the risk of an injury?“

... for you

… for your colleagues

Rare and heavy: e.g. crushing fingers

Frequent but minore.g., splint in finger

Spitzenstetter, F (2006).Optimisme comparatif dans le milieu professionnel: L‘influence de la fréquence et de la gravité sur la perception des risques d‘accient du travail. Psychologie du travail es des organisations, 12, 279-289

n = 45 n = 37


22

Cognitive aspects: Conclusions

> Judgment is often made intuitively quickly!> That‘s often successful – but not always!> We often don‘t call our judgments into question (confirmation bias)

> Routine is indispensable and increases efficiency> BUT: Routine implies less conscious control of actions> Especially under stress and fatigue

We cannot constantly call everyhing into questionBut we can ask at least ONCE:

Is there any information that runs counter to my judgment?

Consider: Workingtime / breaks / fatigue• Ergonomics• Interruptions / distractions• Ensuring controls (e.g, checklists)


24

Special problem:Stress, attention, and team coordination

> Team work implies:> Each member has his/her specific task> At the same time: team coordination must be ensured

> Stress often impairs the team perspective People focus on ONE task

Þ Two tasks:• Individual task• Team-coordination

Example from our simulator studies (cardiac arrest scenario):> Three MDs try to get the defibrillator going> They focus exclusively on the defibrillator> No one continues heart massage…

Tschan, F., Vetterli,M., Semmer, N. K., Hunziker, S., & Marsch, S. C. U. (2011). Activities during interruptions in cardiopulmonary resuscitation: A simulator study. Resuscitation, 82, 1419-1423.

Motivational aspects: Violation of rules


27

Expectancy-Value Theory

Behavior ValueExpectancy

Motivation = S expectancy x Value

“How probable arethe consequences?“

“How desirable arethe consequences?“

desirable results“Should I do that?“

undesirable results

> Not that we calculate our motivation in a strict mathematical sense> But: Intuitively we consider possible consequences, their probability,

and their desirability

A fictituous example…


30

Hygiene: The value-component

Minimize risk

Annoying

+ 10

- 4

In favorof

desinfecting

Minimzing risk = + 10annoying = - 4Time consuming = - 3

Σ = + 3

Timeconsuming

(the next task is waiting)

- 3

Desinfecthands

on the wayto the next

patient?


32

> Aren‘t these rules a bit disproportional?> All I want to do is quickly look at …> If the boss doesn‘t do it, the risk can‘t be that great…> After all, the patient has no open wounds…> I dont‘ want to touch the patient anyway…> I have never had any problems with hygiene…> We don‘t have multi-resistant germs here…

Hygiene: The expectancy component

How great is the risk if I don‘t desinfect?

Desinfecting will minimize the perceived risk only minimally


33

Minimize risk

Annoying

+ 10

- 4

In favorof

desinfecting

Timeconsuming

(the next task is waiting)

- 3

Desinfecthands

on the wayto the next

patient?

Hygiene: Value AND expectancy

0.10

1

1

Minmizing risk = 0.10 * + 10 = 1annoying = 1 * - 4 = - 4time consuming = 1 * -3 = - 3

Σ = - 6

Against


42

Consequences of safe behavior

> delayed> defined by something not

happening> therefore not visible

(“no infections“)> associated with very small risks> which appear even smaller

because we frequently experience that violations haveno serious consequences

> Immediate> annoying> cumbersome> time consuming

Positive consequencesare often

Negative consequences are often

Expectancy componentoften very small

Expectancy component often high

Expectancies can induce us todo things that contradict our values


43

Conclusions

Solution I:

* catheter-related blood stream infections (CR-BSI)

Pronovost, P.J., & Holzmueller, C.G. (2004). Partnering for quality. Journal of Critical Care, 19, 121-129.

All measures are promisingthat make safe behavior

less cumbersome

Example Pronovost I

Problem:> Too many infections of a specific kind in a hospital*> Hygiene identified as cause

Doctors had to collect supplies from 9 (!) different places

Analysing thecourse of events:

Construing a storage cart: Everything in one place

Social Aspects

Communication


49

Sources of errorin communication

My message

will be recieved will be understood as intended will be on everybody‘s mind for a long

time is accepted if no-one raises objections

Feedback


Improving safe behavior through feedback Ende Intervention

100%90%80%70%60%50%

0

Nach Komaki, J. L., Barwick, K. D., & Scott, L. R. (1978). A behavioral approach to occupational safety: Pinpointing and reinforcing safe performance in a food manufacturing plant. Journal of Applied Psychology, 63, 434-445.

Baseline Intervention

Food production (Example: Packaging)

52

Procedure:1. Together with employees: Make list of behaviors that often

are not carried out according to safety rules2. Students observe working behavior3. Intervention: Poster on wall: % safe behaviors from day

before

Start End


54

Making feedback permanent

Workers

Superiors Level I

Superiors Level II

receive feedback about how often they have talked to their workers about safe behavior (referring to teams, not to individuals)

Talk about this information in appraisal interviewsTake it into account for performance evaluation

Clear Effects*:1. More ear protection worn2. Fewer injuries

Maintained after 5 months

Combined with training the following intervention is established

* as compared to a control groupsZohar, D. (2002). Modifying supervisory practices to improve subunit safety: A leadership-based intervention model. Journal of Applied Psychology, 87, 156-163

are interviewed about how often their superior has talked to them about safe behavior

Receive feedback about how often superiors at level 1 have talked with their people about safe behavior

Shared convictions


56

Unquestioned Convictions

Certain safety rules are important / not so important for safety Admitting mistakes is appreciated /not appreciated The boss reacts in an irritated / accepting way if called at

night, even if the situation turns out not to be so bad One‘s intuition can be trusted more than specific gauges and

monitors Management gives safety priority over productivity Certain behaviors are „safe“ or „risky“

Social Norms

Social consequences of behavior that does, or does not, conform to

safety rules


59

NORMS

Team

Safety

Avoid conflict

Be competent

Performance/ Production

Dont‘ tell on others

Keep out of others‘ domain

Quality

Respect rules

Don‘t appear anxious


60

Violating social norms

> Violating social norms frequently is punished> e.g., > by critizising> by ridiculing> by social exclusion

> Expecting (dis-)approval influences the expectency-value calculation> creates expectancies (“they will laugh about me“)> These expectancies are associated with desirability

> being laughted about is unpleasant; > being acknowlegded as competent is pleasant


61

Social Norms: Hierarchy

Sometimeswe ask too few questions

andinsist (too) litte

especially, if the others– react in an irritated way– are hierarchically higher– might think of us as incompetent

Typical example: Co-Pilot notices pilot error• does not say it• says it, but not loud enough• does not insist if pilot reacts defensively


62

Dangerous instructions

A nurse gets a call from a medical doctor:

She is to administer a drug to a patient> The nurse does not know the doctor; he is not on any list of

hospital personnel> The drug has to be obtained from the hospital pharmacy> The dose is clearly too high

Of 22 nurses, 21 would have given the drug

Follow-up study:Of 18 nurses, 9 would have given the drug

Hofling, C.K., Brotzman, E., Dalrymple, S., Graves, N., and Pierce, C. M. (1966). An experimental study of nurse- physician relationships. Journal of Nervous and Mental Disease, 143, 171-180. Rank, S.G. & Jacobson, C.K. (1977). Hospital nurses’ compliance wit medication overdose orders: A failure to replicate. Journal of Health and Social Behavior, 17, 188-193.


64

Making feedback permanent: Example II

• Solution I: Cart for material (see above)

• Soluation part Teil II: The social aspect

* catheter-related blood stream infections (CR-BSI)

Pronovost, P.J., & Holzmueller, C.G. (2004). Partnering for quality. Journal of Critical Care, 19, 121-129.

Problem: Too many infections due to insufficient hygiene

• Proposition:• Nurses

• observe behavior of MDs• fills in checklist• If necessary: interrupts and reminds the MD of the

hygiene rules

• Implementation: • Cumbersome: long discussions; much resistance• But: Finally accepted

• Result: Infections reduced by 96%


65

Admitting mistakes:Calculating expectancies

What happens if I report it?- I lose face- Many will say: This should not have happend- Many will say: “This would not have happened to me “

+ I am honest

What happens if I don‘t report it?- If I am caught, I lose even more face+ If I am not caught, my reputation remains good+ If I report it, I have to go through a lot of bureaucracy- I am not honest

I have made a mistake – should I report it?

Expectancy-value calculation: If there is a chance to cover it up, that‘s often „worthwhile“

Frequently there are more positive than negative consequences when one does not report the mistake


66

Mistakes in hindsight

In hindsight people tend to think: That result was to be expected (Hindsight-Bias)

We tend to see causes- too much within the person:

“he did not pay enough attention “; “she was not careful enough“

- too little in the situation:„he was distracted “; “the situation appeard harmless “

This tendency is especially strong when we are dealing with other people‘s behavior:

He did not pay attention – I was distracted

Hindsight bias fosters blaming!


69

Safety culture / error culture

Mistakes often are• a taboo• associated with blame• an attack on one‘s Ego

> It therefore is difficult to discuss mistakes openly

But: Mitstakes can never fully avoided> We therefore have to

• expect mistakes• Regard mistakes as normal• Discuss mistakes openly; not primarily by blaming

• Which does not imply that acts of gross negligence should be accepted


70

> An open, trustful climate> is the best precondition> for discussing mistakes openly

> Open discussion about mistakes

1. helps to avoid mistakes

2. And – since mistakes can never be fully avoided:> helps to detect mistakes early> and to prevent grave consequences

Safety culture / error culture

Error management is as important as error prevention


71

“Defense in depth“

Technicalbut also human

The „Swiss Cheese“

Reason, J. (2000). Human error: models and management. British Medical Journal, 320, 768-770.


74

Human error

TechnicalFailure(latentErrors)

Humanrescue

acts

Technicalcorrections

Success?

Result OK

Graveconse-

quences

+

-

Human errorHumanrescue

acts

Humans are not only the weak points

... but also often the ones who prevent

catastrophes

> These human resources have to be strenghened!

Thank you very much!

Human Error- or why the real surprise is that so little goes wrong

Norbert K. Semmer

University of BernPsychology of Work and Organizations

SwissTransfusionSeptember 6, 2013


77


78

Gründe für unsicheres Arbeiten Antwort-Beispiele aus kanadischer Interview-Studie

Eine Person, die zu schwere Säcke trägt: „Ich habe meine eigenen Interessen hinten angestellt. Es war mir wichtiger, dass die anderen zufrieden waren mit der Art, wie ich meine Arbeit machte.“

„Er denkt, er wirkt wie ein Schwächling, wenn er die Sicherheitsausrüstung trägt.“

Jemand wollte eine Arbeit wegen Sicherheitsbedenken nicht ausführen: „Wir haben ihn nachher zur Rede gestellt ... Wir haben ihm klar gemacht, was Sache war, und wenn er das noch einmal machen sollte, dann würden wir dem Chef sagen, dass wir nicht mehr mit ihm arbeiten wollen. Er war einfach ein Feigling.“

Mullen, J. (2004). Investigating factors that influence individual saftey behavior at work. Journal of Safety Research 35, 275-285.


79

Eine Handlung, die man zu zweit ausführen muss...

Was passiert, wenn ich ihn frage? Er könnte glauben, ich kann das nicht alleineEr ärgert sich, weil er aus der Handlung gerissen wirdEs kann dauern, bis er Zeit für mich hatEs passiert sicher nichtsIch halte die Vorschrift ein

Was passiert, wenn ich nicht frage?Bei meiner Erfahrung kann doch gar nichts schief gehenIch kann zeigen, dass ich das auch alleine kannIch kann zeigen, dass ich nicht ängstlich binEs geht alles schnellerIch verletze die Vorschrift

Ein Kollege ist in der Nähe. Er hat gerade viel zu tun. Soll ich ihn fragen, mir zu helfen?


86

Fehlertypen

BeabsichtigteHandlungen

Sicherheitsgefährdende Handlungen

Sicherheits-

gefährdende

Handlungen

UnbeabsichtigteHandlungen

Patzer(slips)

Schnitzer(lapses)

Fehler(mistakes)

Verstoss

Aufmerksamkeitsfehler• Störung• Vertauschung• Fehlanordnung• Zeitliches Missmanagement

Gedächtnisfehler• Unterlassung geplanter Schritte• Verlust des aktuellen Standes der Dinge

• Vergessen der ursprünglichen Absicht

regelbasierte Fehler• Falsche Anwendung einer guten Regel

• Anwendung einer schlechten Regel

wissensbasierte Fehler• viele verschiedene Formen

Reason, J. (1994). Menschliches Versagen: Psychologische Risikofaktorenund moderne Technologien (p. 255). Heidelberg: Spektrum.


87

Skill-basedSensumotorische Regulation

Schnitzer / Patzer

Knowledge-basedIntellektuelle Regulation

Wissensbasierte Fehler (Irrtümer)

Rule-basedFlexible Handlungsmuster

Regelbasierte Fehler

Fehler und Regulationsebenen


88

Kontrollebene unddominierende Fehlerart

Fehlerarten und fehlerbeeinflussende Faktoren auf verschiedenen Kontrollebenen IZimolong (1990), erweitert nach Rasmussen, 1982; Reason, 1986

Fehlerauslösende Bedingungen

• Zeitliche Nähe und Häufigkeit in der vorherigen Nutzung (Gewohnheit, Stereotypisierung

• Unbeabsichtigte Auslösung durch gemeinsame Merkmale (Assoziationsfehler)

Sensumotorische Regulation:Handlungsfehler

Zimolong, B. (1990). Fehler und Zuverlässigkeit. In C. Graf Hoyos & B. Zimolong (Hrsg.), Ingenieurpsychologie. Enzyklopädie der Psychologie, Themenbereich D, Serie III, Bd. 2, (S. 313-345). Göttingen: Hogrefe. (Tab. 6, S. 326)


89

Regelebene:Verwechslungs- oderBeschreibungsfehler

Fehlerarten und fehlerbeeinflussende Faktoren auf verschiedenen Kontrollebenen IIZimolong (1990), erweitert nach Rasmussen, 1982; Reason, 1986

Kontrollebene unddominierende Fehlerart Fehlerauslösende Bedingungen

Regelebene:Verwechslungs- oderBeschreibungsfehler

• Einstellung: schematische Sichtweise („Das haben wir schon immer so gemacht“)

• Repräsentativität von Sachverhalten und Lösungsmustern („Das hatten wir schon“)

Zimolong, B. (1990). Fehler und Zuverlässigkeit. In C. Graf Hoyos & B. Zimolong (Hrsg.), Ingenieurpsychologie. Enzyklopädie der Psychologie, Themenbereich D, Serie III, Bd. 2, (S. 313-345). Göttingen: Hogrefe. (Tab. 6, S. 326)


Diagnostic performance of physicians

> Main diagnosis incorrect in 25-45% of cases (Autopsy studies: Shojania et al., 2003; Cameron et al., 1980)

> Causes of diagnostic failures— Person factors

– from overconfidence to lack of experience

(Graber, 2005, Redelmeer, 2005, Croskerry, 2005, Kuhn, 2002)

— Context factors – fatigue, emergency etc.

(Croskerry & Sinclair, 2001, Espinosa & Noaln, 2000; Guly, 2001; Hallas & Ellingsen, 2006)

— Cognitive biases – Tversky and Kahneman (Croskerry, 2002)

— Absence of reasoning (Denig, 2003, Kuhn, 2002)


Procedure

> High fidelity patient simulator, groups of three (two) MDs> Patient transferred from Emergency Room

— Oral information given by the ER-resident (confederate)– Pneumonia, treated with an IV antibiotic (penicillin)

— Hands over the patient file to one group member— Correct diagnosis

– Patient is allergic to penicillin and reacts with a severe anaphylactic shock, situation fatal within minutes

> Ambiguous condition: – Confederate also reports failed attempt to put a subclavian IV access

— Plausible, but wrong diagnosis– Attempt of subclavian access caused left tension pneumothorax (collapsed

lung on left side), dangerous


Distinguishing analphylactic shock from tension pneumothorax

Shared symptoms Shortness of breath, caughing, low oxygen saturation, low blood pressure, dizziness

Distinguishing symptoms

Tension pneumothorax: • no breathing sound in

affected lung• Chest pains• …

Anaphylactic Shock • Bronchospasm• Ventricular tachycardia• …


Hypotheses

1. Task ambiguity influences error rate: – In a more ambiguous situation teams fail the correct diagnosis more often

2. Diagnostic reasoning influences quality of diagnosis— Groups that find the correct diagnosis

– have a more extensive data gathering phase (i.e. read the patient file; consider more aspects for diagnosis)

– have a more explicit reasoning process– Communicate limits of knowledge – Meta-communication about diagnostic process– More causal reasoning (e.g. if- then; because, therefore)– Talking to the room (Artman & Waern, 1998)

3. Signs of confirmation bias?


Situational Ambiguity (distracting information) and Diagnostic Performance

16

1

2

6

8

6

Correct diagnosis Correct diagnosis with help Missed diagnosis

N=39 groups; Chi2(2)=11.97, p=.002High ambiguity (distractor): N = 20 groupsLow ambiguity (no distractor: N = 19 groups

Distractor Distractor DistractorNo

Distractor NoDistractor

NoDistractor

Serious diagnostic shortcomings: Low ambiguity: 3 / 19 = 16% High ambiguity: 14 / 20 = 70%

all further analyses: high ambiguity situation only


Hypotheses

1. Task ambiguity influences error rate: – In a more complex situation teams fail the correct diagnosis more often

2. Diagnostic reasoning influences quality of diagnosis

Groups that find the correct diagnosis have a more extensive data gathering phase

(i.e. read the patient file; consider more aspects for diagnosis) have a more explicit reasoning process

Communicating limits of knowledge Meta-communication about diagnostic process More causal reasoning (e.g. if- then; because, therefore) Talking to the room (Artman & Waern, 1998)

3. Signs of comfirmation bias?


Gathering information: Aspects considered before the first diagnosis is made (correct or not)

2.0

2.4

1.8

0.0

0.5

1.0

1.5

2.0

2.5

correct with help missed

Number of diagnostic aspects mentionedbefore first diagnosis

n.s.

Not significant; hypothesis not confirmed


Reasoning: insecurity and meta-communication

> Number of statements of insecurity made before the first diagnosis— less than one per group— no significant differences

> Meta-communication (reflecting about the diagnostic process)— less than one statement per group— no significant differences


Reasoning before first diagnosis was made(if-then / because / therefore, etc. )

F(2)=5.75, p=.014, R2adj.=.35; Bonferroni: correct different from help, missed. 2 groups that diagnosed based on the file are excluded from this analysis

4.0

1.11.0

0.0

1.0

2.0

3.0

4.0

5.0

correct help missed


Reasoning: Talking to the room

correct with help missed0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.8075%

13%

0.00

F(2)=6.859, p=.008, R2adj.=.41; Bonferroni: correct different from help, missed. 2 groups that diagnosed based on the file are excluded from this analysis


Hypotheses

1. Task complexity influences error rate: – In a more complex situation teams fail the correct diagnosis more often

2. Diagnostic reasoning influences quality of diagnosis— Groups that find the correct diagnosis

– have a more extensive data gathering phase (i.e. read the patient file; consider more aspects for diagnosis)

– have a more explicit reasoning process– Communicate limits of knowledge – Meta-communication about diagnostic process– More causal reasoning (e.g. if- then; because, therefore)– Talking to the room (Artman & Waern, 1998)

3. Signs of confirmation bias?


Signs of conformity

> After pneumothorax diagnosis was suggested, some physicians auscultated several times before «hearing» differences: — Contagious illusion or conformity?

> Some physicians do not communicate but show behavioral signs of disagreement— E.g., one physician

– stops the penicillin

– « murmurs » that it might be an anaphylactic shock

S=refers to page Bizzari


104

Spezielle Probleme


105

Der Multitasking-Mythos:Autofahren und Telephonieren

> Echtes Multitasking allenfalls möglich, wenn eine Komponente hoch automatisiert ist

> Ansonsten: Multitasking = Schneller Aufmerksamkeitswechsel(Loukopoulos & Dismukes, 2009)

Loukopoulos, L. D., R. D. Dismukes, et al. (2009). The multitasking myth. Handling complexity in real-world operations . Burlington, VT:, Ashgate. Redelmeier, D. A., & Tibshirani, R. J. (19979). Association between celluar-telephone calls and motor vehicle collisions. New England Journal of Medicine, 336, 453-458.Strayer, D. L., Drews, F. A., & Crouch, D. J. (2006): a comparison of the cell phone driver and the drunk driver. Human Factors, 48, 381-391.

> Telephonieren während des Autofahrens erhöht das Unfallrisiko> Gilt auch bei freihändigem Telephonieren!

> Problem der Aufmerksamkeit, nicht des Handling> Risiko vergleichbar 0.8‰ Alkohol (Redelmeier & Tibshirani, 1997; epidemiologische Studie)

> Experimentelle Studie: (Strayer et al., 2006) > Handy: mehr Auffahrunfälle, längere Reaktionszeit

> Unfallrisiko ca. 5 x höher.> Kein Unterschied freihändig / manuell> Vergleichbarkeit des Risikos mit Alkohol (0.8‰) bestätigt


107

Ergebnisse Zohar ISicherheitsgespräche und Gehörschutz

Figure 1. Interrupted time-series data of supervisory safety practices and earplug use. exp. experimental group; cont. control group.

Gehörschutz

Interaktionen

Gehörschutz

Interaktionen

Zohar, D. (2002). Modifying supervisory practices to improve subunit safety: A leadership-based intervention model. Journal of Applied Psychology, 87, 156-163

NachmessungenInterventionBaseline

Kontrollgruppe

Experimentalgruppe


Interaction between Exp. condition and treatment phase (microaccident rate)

> 0.0

> 0.5

> 1.0

> 1.5

> 2.0

> 2.5

> AFTER > BEFORE

Exp. Group

Control Group

Zohar, D. (2002). Modifying supervisory practices to improve subunit safety: A leadership-based intervention model. Journal of applied psychology, 87, 156-163.

INJ

UR

Y R

AT

E


111

Ereignis Subjektive Repräsentation des Ereignisses

Operator

Unfall Objektive Regelwidrigkeit, die zumindest post-hoc erkannt wird Abschwächung

„Beinahe“ - Unfall

Regelwidrigkeit ist subjektiv bekannt

„Beinahe“- Unfall wird erkannt Abschwächung

„Beinahe“- Unfall wird nicht erkannt

Negative Verstärkung*

Regelwidrigkeit ist subjektiv nicht bekannt

„Beinahe“- Unfall wird erkannt Abschwächung

„Beinahe“- Unfall wird nicht erkannt

Positive Verstärkung

Verstärkung und Abschwächung regelwidrigen Verhaltens:„Unfall“ & „Beinahe-Unfall“, deren subjektive Repräsentation und der resultierende lerntheoretische Operator

Nach: Musahl, H.-P. (1997). Gefahrenkognition: Theoretische Annäherungen, empirische Befunde und Anwendungsbezüge zur subjektiven Gefahrenkenntnis. Heidelberg: Asanger. [Tab. 29; S. 381]

*Negative Verstärkung sensu Skinner: Verhalten wird verstärkt durch das Ausbleiben (oder Beendigung) einer Bestrafung


Safety Climate: Organization Level(1 = completely disagree – 5 = completely agree)

Top management in this plant – company1. Reacts quickly to solve the problem when told about safety hazards.2. Insists on thorough and regular safety audits and inspections.3. Tries to continually improve safety levels in each deparment.4. Provides all the equipment needed to do the job safely.5. Is strict about working safely when work falls behind schedule.6. Quickly corrects any safety hazard (even if it‘s costly).7. Provides detailed safety reports to workers (e.g., injuries, near accidents).8. Considers a person‘s safety behavior when moving-promoting people.9. Requires each manager to help improve safety in his-her department.10. Invests a lot of time and money in safety training for workers11. Uses any available information to improve existing safety rules.12. Listens carefully to workers‘ ideas about improving safety.13. Considers safety when setting production speed and schedules.14. Provides workers with a lot of information on safety issues.15. Regularly holds safety-awareness events (e.g., presentations, ceremonies).16. Gives safety personnel the power they need to do their job.

Note. Items cover three content themes: Active Practices (Monitoring, Enforcing), Proactive Practices (Promoting Learning, Development), and Declarative Practices (Declaring, Informing).

Zohar, D., & Luria, G. (2005). A multilevel model of safety climate: Cross-level relationships between organization and group-level climates. Journal of Applied Psychology, 90, 616-628.


My direct supervisor1. Makes sure we receive all the equipment needed to do the job safely.2. Frequently checks to see if we are all obeying the safety rules.3. Discusses how to improve safety with us.4. Uses explanations (not just compliance) to get us to act safely.5. Emphasizes safety procedures when we are working under pressure.6. Frequently tells us about the hazards in our work.7. Refuses to ignore safety rules when work falls behind schedule.8. Is strict about working safely when we are tired or stressed.9. Reminds workes who need reminders to work safely.10. Makes sure we follow all the safety rules (not just the most imortant ones).11. Insists that we obey safety rules when fixing equipment or machines.12. Says a „good word“ to workers who pay special attention to safety.13. Is strict about safety at the end of the shift, when we want to go home.14. Spends time helping us learn to see problems before they arise.15. Frequently talks about safety issues throughout the work week.16. Insists we wear our protective equipment even if it is uncomfortable.

Note. Items cover three content themes: Active Practices (Monitoring, Controlling), Proactive Practices (Instructing, Guiding), and Declarative Practices (Declaring, Informing).

Zohar, D., & Luria, G. (2005). A multilevel model of safety climate: Cross-level relationships between organization and group-level climates. Journal of Applied Psychology, 90, 616-628.

Safety Climate: Group Level(1 = completely disagree – 5 = completely agree)

Vielen Dank!

Documents

Psychology of Work and Organizations, N. K. Semmer Norbert K. Semmer University of Bern Psychology of Work and Organizations 1 Geneva September 6, 2013