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Adi-ances in Nurstnn Science Vol. 28, No. 2. pp. l27-liS6 © 2(HIS Uppinc-oti WUIUma & Wilkins. tut

From Practice to Midrange Theory and Back Again Beck's Theory of Postpartum Depression . . ,

Gerri C. Lasiuk, MN, RN; Linda M. Ferguson, MN, RN

This article presents a brief overview of theory as background for a more detailed discussion of midrange theory—its origins, the critical role for midnmge theory in the development of nursing practice knowledge, and the criteria for evaluating midrange theory. We then chron- icle Chery! Tatano Beck's program of research (jn postpartum depression (PPD) and advance the thesis that her theory of PPD. titled Teetering on tbe Edge, is an exemplar of a substantive midrange nursing theory. We demonstrate Beck s progression from identification of a clin- ical problem to exploratory-descriptive research, to concept analysis and midrange theory development, and fmally to the application and testing of the theory in the clinical setting, riirough ongoing refmement and testing of her theory. Beek has increased its genenilizabitity across various practice settings and continually identifies new issues for investigation. Beck's program of research on PPD exemplifies using nursing outcomes to build and test nursing practice knowledge. Key words; Cheryl Tatano Beck, middle range theory, nursing prac- tice theory, nursing outcomes, nursing theory, pnstpartutn depression

IN today's world of evidence-based nurs-ing and kmm'ledge utilization, few ques- tion the centrality of theory to nursing knowl- edge deveiopment and the importance of that process to the ongoing evoltition of the dis- cipline. Although even Florence Nightingale knew that the practice of nursing requires specialized, discipline-specific knowledge,' it would be several decades before the science of nursing had evolved sufficiently to sys- tematically develop that knowledge. In the early part of the last century, nursing prac- tice knowledge took the form of "rules, prin- ciples, and traditions"'̂ P '̂*^ derived from ex-

From the Faculty of Nursing, llniuersity of Alberta, Edmonton, AH (Ms iMsiuk), and the CoUege of Nursing. University of Saskatchewan, Saskatoon, SK (Ms Ferguson), Canada.

Corrvsfxmding author: Gerri C. Lasiuk, MN, RN. Faculty of Nursing. Uniivrsity of Alberta, .ird Floor, Clinical Sci- ences lildg, Edmonton. AB, Canada T6G 2G3 (e-mail: gerri. lasiuk ® ualbertu. ca).

perience and taught by rote. Tlie compe- tent practitioner needed only a caring dis- position coupled with a handful of techni- cal skills, which were taught in hospital-based apprenticeship-training programs. The little theoretical knowledge that did exist in nurs- ing was co-opted from other disciplines.

This situation began to change when the public health movement took hold in the Western world. By 1913, the National League for Nursing Education in the United States recognized that the increasing scope and complexity of nursing practice required a broader knowledge base that must include "some knowledge of the scientific approach to disease, causes, and prevention "2(p60) The social upheaval that accompanied two world wars and the intervening Depression years spawned major shifts in the social or- der; changes to the delivery of healthcare; and a growing demand for skilled nurses. In re- sponse, national governments invested new resources into the study of nurse education and work life. This was a critical juncture

127

128 ADVANCES IN NURSING SCIENCE/APRIL-JUNE 2005

for the discipline because it presented both an opportunity and an imperative for nurses to articulate the nature of the discipline, to define its domain, and to set a course for future development. Consideration of these weighty issues precipitated a cascade of events that culminated in a consensus about the need for a body of distinctly nursing knowledge, developed and tested through research (for reviews, see references 1 and 3).

Tlie importance of theorj' to nursing knowledge development received official sanction in 1965 when the American Nurses Association (ANA) issued a position paper declaring theory development to be the pri- mary goal of the profession.^ Nursing schol- ars responded and the earliest nursing the- ories went to press in the iate 1960s and through the 1970s. These highly abstract grand theories and conceptual models de- fined the boundaries of the discipline and established the theoretical foundations for nursing curricula.'** While many practic- ing nurses saw them as having little direct relevance to their work, their articulation was a necessary precondition for subsecjuent phases in nursing knowledge development.' In their seminal article, Dickoff et al"̂ reit- erated the theory-practice gap and sketched out a course for the development of research- based knowledge to guide nursing practice. At the same time, the sociologist Merton^' in- troduced the notion of middle-range theory as a means to guide empirical inquiry and to test that discipline's organizing theories. Jacox^ would later endorse middle-range theory de- velopment as an important vehicle for the de- veiopment of practice knowledge needed in nursing.

By the late 1980s, nursing was primed to respond to Meleis'* '̂''̂ ^* impassioned plea for a "reVisioning" of the goals of nursing schol- arship. For the discipline to go forward, she said, it must refocus its efforts on developing substantive nursing knowledge built on con- cepts grounded in practice. This marked the entry of nursing into the current era, one in which the main thrust is toward the gener-

ation and testing of midrange and situation- specific theory.

This article opens with a brief review of theory as a way to create a context for a more detailed discussion of midrange theory—its origins, the critical role for midrange the- ory in the development of nursing prac- tice knowledge, and criteria for evaluating midrange theory. We then chronicle Cheryl Tatano Beck's program of research on post- partum depression (PPD) and advance the thesis that her theory of PPD, titled Teeter- ing on the Edge, is an exemplar of a sub- stantive midrange nursing theor>'. We demon- strate Beck's progression from identification of a clinical problem, to exploratory descrip- tive research.^"'- to concept analysis'^ and midrange theory development,'^ and finally to the application and testing of her theor\' in the clinical setting.''^"'" Through ongoing re- finement and testing of the theory. Beck has increased its utility and applicability across various practice settings and continually iden- tifies new issues for investigation. This re- search program on PPD exemplifies of using nursing outcomes to develop practice knowl- edge through midrange theory development.

THEORY: A PRIMER ' '•

Chinn and Kramer describe theory as the "creative and rigon)us structuring of ideas that projects a tentative, purposeful, and systematic view of phenomena."'*f'"* More specifically, it consists of concepts and the relationships among those concepts, for the purpose of describing and explaining the phe- nomenon, predicting outcomes, or prescrib- ing nursing actions.-^''^^" Theory serves to organize disciplinary knowledge and to ad- vance the systematic development of that knowledge.^ It may also identify' the param- eters of a discipline; provide a means for ad- dressing disciplinary problems; furnish a lan- guage with which to frame ideas of interest to a discipline^; and provide unifying ideas about phenomena of interest to a discipline.'"

By its nature, theory' is abstract and does not exist in the material world per se; rather.

From Practice to Midrange Theory and Back Again 129

it is a mental conception or an idea that rep- resents things or events in that world. Be- cause it is abstract, theory does not necessar- ily represent a particular thing or event, but may refer more generally to a class of simi- lar things or events. In contrast, something that is concrete does exist in material form and "is embodied in matter, actual practice, or a particular example.'* '̂ In elucidating the nature of a particular theory, we might con- struct an imaginary line or continuum (an ab- straction in itself!) anchored on one end by things or events thai are concrete and on the other by things or events that are abstract. Theories that are relatively more abstract arc broader in scope and can be generalized to a greater number of things or events, whereas those that are more concrete are narrower in scope and applicable to a smaller range of phenomena.

A concept is "a complex mental formula- tion of experience.""P**'* It is the totality of a phenomenon, as it is perceived and—if it is empiric—can be verified by others. Like theories, concepts also exist at varying lev- els of concreteness and abstractness. A con- cept such as "biological sex" is more con- crete (or empiric) because we can directly t)bserve evidence of it. On the other hand, phenomena that can be measured only in- directly (such as depression) are somewhat more abstract and exist somewhere in the middle of our continuum. At the other end of the scale are highly abstract concepts like "self esteem" or "social support." Measure- ment of these concepts is also done indirectly, via agreed-upon indicators. The relationships between and among the concepts of a theory are stated -AS propositions} These are "postu- lates, premises, suppositions, axioms, conclu- sions, theorems, and hypotheses,"'"'̂ *** each of which reflects the proposition's purpose, t>'pe of logic used in its construction, and the context in which the propositions occurs.

Types of theory

Having described key elements of theory, we can begin to label theories on the basis of

their nature and purpose. Here we will con- sider metatheories, grand theories, midrange theories, and situation-specific theories.

Metatheory is global in nature and stipu- lates, in the broadest terms, the phenomena of interest to a discipline. Because of its high degree of abstraction, metatheory does not lend itself to empirical testing. This level of theory furnishes the concepts and proposi- tions that are epistemological building blocks for disciplinary knowledge development. To a lesser degree than metatheory, grand the- ory is also very abstract. It offers conceptual frameworks, which define and organize disci- plinary knowledge into distinct, though still broad, perspectives.'

The sociologist Merton*̂ introduced the no- tion of middle range theory as a tool for em- pirical inquiry. He described it a "limited set of assumptions from which specific hypotheses are logically derived and confirmed by empir- ical investigation.•̂ '̂ P'̂ '*** Midrange theories are less abstract and more limited in scope than grand theories. They involve fewer concepts, have clearly stated propositions, and readily tend themselves to the generation of testable hypotheses. ̂^

Situation-specific or microtheories focus on specific phenomena in a particular set- ting. They are very limited in scope and are not intended to transcend time, place, or social-political structure.^ Two such nurs- ing theories are Gilliland and Bush's^^ the- ory of social support for family caregivers and Im and Meleis'̂ -̂ theory of Korean immigrant women's menopausal transition.

MIDRANGE THEORY

A major limitation of grand-theory is that its concepts are too broad and abstract for em- pirical testing. In contrast, situation-specific or single-domain theories-̂ contribute little to building a cohesive and unified body of dis- ciplinary knowledge because they are very concrete and too narrow in scope. Merton*' argues that middle range theory circum- vents both of these problems. To his way of

130 ADVANCES IN NURSING SciENCE/APRa-JUNE 2005

thinking, efforts to explicate a unifying grand theory in sociology had just the opposite effect. That is, they resulted in the proUf- eration of a "multiplicity of philosophical systems in sociology and, further, led to the formation of schools, each with its cluster of nia.sters and disciples.•*^ '̂'̂ * Merton believes that sociology's advance as a discipline rests on the development of middle-range theory whereas continued focus on total sociologi- cal systems (ie, grand theories) impede that progress. In nursing, early efforts to define the parameters of nursing's domain and to identify its phenotnena of interest led to the development of metatheory and grand- theory While these did serve to differenti- ate nursing from other disciplines and expli- cated the discipline's ontological values, they provided little direction for nursing research to say nothing of the day-to-day practice of nursing. •

According to Merton,*' middle range the- ory can be developed from grand-theory (de- ductively) or from empirically grounded con- cepts (inductively). He emphasized, however, that the strength of middle-range theor>' is its capacity to describe, explain, and make pre- dictions about concrete phenomena of inter- est to a discipline. The range of theoretical problems and testable hypotheses generated by middle range theory potentates its util- ity and productivity. While Merton beUeves that the larger conceptual schemes of the discipline should evolve from the concep- tual consolidation of tested middle-range the- ories, he does not advocate exclusive focus on them.

Early nursing advocates of midrange theory "̂* envisioned that a particular midrange theory might support a single or multiple grand-theories, thus cohering nursing knowledge. As well, Codŷ ** suggests that midrange theory testing provides a way to analyze the adaptability of nonnursing theories to nursing practice. On a cautionary note, however, he adds that researchers and clinicians must first determine whether this borrowed theory is consistent with the

ontological values of nursing. If it is not, he warns, it will not advance nursing science.

' -• r

Evaluating Midrange Theory

In a 1993 address to the ANA's Council of Nurse Researchers Symposium, Suppe pro- posed that midrange theory is identifiable by its scope, level of abstraction of the concepts, and testability.-'' The scope or generalizahil- ity of a theory refers to the range of phe- nomena to which the theory applies' or to the number of situations addressed by a par- ticular theory.^ Because midrange theory is more concrete than grand theory—but less so than situation-specific theory—it applies across several client populations and practice settings, but not to all.'•'''•^^ The concepts of a midrange must be clearly delineated and suf- ficiently concrete as to be testable.''''•^"•^'''^" Testability requires that these concepts can be coded objectively, as operational definitions, empirical measures, or hypothesized relation- ships, and that researchers can test the rela- tionships between and among these concepts under different conditions.'''-''••^^

In the following section, we exatnine Cheryl Tatano Beck's theor)' of PPD. Our method for doing this is adapted from an approach to theory analysis described by Meleis^ and on the more specific crite- ria for analysis and evaluation of midrange theory proffered by Whall.̂ '̂ Meleis' ap- proach encourages attention to the tbeo rist's background and important life influ- ences; the paradigmatic origins of the theory; as well as analysis of the theory's nitionale, scope, goal, and system of relations among other factors. This provides a context for the theory, locates the theorist in the larger scientific community, and fosters an under- standing of where their work resides within the disciplinary knowledge structure. On the other hand, Whail s approach to theory eval- uation is more directly oriented to an analy- sis of whether or not a theory bears the char- acteristics of a midrange theory. The latter considers (1) the assumptions underlying the

From Practice to Midrange Theory and Back Again 131

theory; (2) the relationship of the theory to philosophy of science; (3) any loss of infor- mation due to concepts not being interrelated via propositions; (4) presence/absence of in- ternal consistency and congruence among all components of the theory; (5) empirical ad- equacy of the theory; and (6) evidence as to whether it has been tested in practice and/or through research and has held up to tliat scrutiny.

TEETERING ON THE EDGE: IS IT A MIDRANGE NURSING THEORY?

Beck's background and life influences

According to her curriculum vitae,^" Beck received a bachelor s degree in nursing in 1970 from Western Connecticut State Univer- sity. Two years later, she earned a master's degree in both maternal-newborn nursing and nurse-midwifery from Yale University. She specifically chose the Yale program be- cause of this blend of research training and clinical specialization (written communica- tion, November 25, 2002). A decade later, in 1982, Beck completed a doctorate in nurs- ing science from Boston University. During that time, we see foreshadowing of Beck's later interest in PPD. The firsi of these is an article^' examining the contributions of role conflict and learned helplessness to women's depression. The second comes during her doctoral research (involving time perception during labor and delivery) when she is in- trigued to discover a link between depression and alterations in time sensibility (written communication, November 25, 2002). Ten years later, in an analysis of maternal-newborn nursing Htenitiire published between 1977 and 1986.'̂ Beck concluded that nurse re- searchers need to aim for methodological con- gruence in their choice of researeh designs; that the reliability and validity of instruments employed in maternal-child research must be evaluated; and that maternal-child nurse re- searchers need to identify areas of potential research.

Paradigmatic origins of the theory

Beck's initial study in the area of PPD ex- plored early discharge programs in the United States through a literature review and cri- tique, in which she identified a significant gap in maternal care. She wrote:

What has not been given equal priority in post- partum follow-up care, however, is the mother's psychological status, more spccificaUy, the phe- nomenon of maternity blues. Early discharge moth- ers are at home when the blues usually occur during the first week after delivery. Specific assess- ments for maternity blues should routinely be part of the nurse s assessment of these mothers during home visits.

Tlie next year, she reviewed the existing lit- erature on maternity blues" and began clar- ifying the differences among the concepts of postpartum psychosis, postpartum deptvs- sion, and maternity blues- She also identi- fied the need to improve the instruments em- ployed in this area and called for "both quali- tative and quantitative research designs . . . to completely investigate the phenomenon of the blues. ""

Beck̂ '̂ takes exception to the notion that qualitative research belongs exclusively to the early stage of a re.search program. She con- tends that at the initset of a research pro- gram it is impossible to predict its trajectory. Rather, she says, the "path of a nurse scien- tist's research program is truly determined by the state of knowledge that is known at each juncture when the research questions for the next study are being determined."^-'f'-*''" In response to Morse ŝ ^ caution against inves- tigators moving back and forth between in- ductive and deductive research approaches at the expense of methodological rigor. Beck counters that researchers can acquire the knowledge and skills about a variety of re- search methods through continuing educa- tion and/or via collaboration with others who have the methodological expertise needed for a particular study. In her rejection of the incommensurability of different inquiry perspectives, she provides the basis for her

132 ADVANCES IN NURSING SCIENCE/APRIL-JUNE 2005

program of research: the need to address the question that arises with the most appropri- ate research method.

Philosophical foundations

Beck reflects characteristics of a postmod- ern philosophy of science. Many postmod- ernists are also constructivists who believe that each of us constructs an imderstanding of the material world on the basis of our perceptions of it. Because observation and perception are fallible, these understandings are inviiriably incomplete. Our best hope for approximating a full understanding of phe- nomena of interest, is through systematic re- search employing multiple methods. Accord- ing to Beck. "Each successive research project should be guided by the previous research study. Tlie objective of this systematic, con- tinuous inquiry is the cumulative production of new knowledge in a substantive area of nursing. "̂ <̂P̂ ''̂ >

1

Scope of the theory

In 1992, Beck'^ published a phenomeno- logical study of the lived experience of PPD. Data for the study were the text of tran- scribed interviews with women attending a PPD support group, which Beck cofacilitated for a number of years. From those. Beck identified 45 significant statements about the women s experience of PPD and clustered them into the following 11 themes, which ex- plicate the "fundamental structure of postpar- tum depression"'̂ '̂̂ ***:

1. Unbearable loneliness 2. Contemplation of death provides a

glimmer of hope 3. Obsessive thoughts about being a bad

mother 4. Haunting fear that "normalcy" is irre-

trievable 5. Life is empty of all previous interests

and goals 6. Suffocating guilt over thoughts of

harming their infants 7. Mental fogginess

8. Envisioning self as a robot, just going through the motions

9. Feeling on the edge of insanity due to uncontrollable anxiety

10. Loss of control of emotions 11. Overwhelming feelings of insecurity

and the need to be mothered The next year Beck'^ extended those find-

ings into a grounded theory of PPD, titled Tee- tering on tbe Edge. She chose a qualitative approach to the topic because she believed that the Beck Depression Inventory (BDl),^' a widely used instrument to detect depression, failed to accurately capture the "horrifving ex- periences" (written communication, Novem- ber 25, 2002) of PPD that she saw in her clini- cal practice. Research evidence corroborated Beck sobservations,'''-^'^' calling into question the content validity of the BDI for PPD and identified a need for further investigation.

Beck s grounded theory inquiry involved a purposive sample of women attending her PPD support group. Data were collected over a period of 18 months and included field notes from the support group meetings and transcriptions of in-tlepth interviews with 12 of the group s participants, liirough con- stant comparative analysis. Beck identified the core variable or basic psychological problem in PPD as being ioss of control, which the women experienced as teetering on the edge of insanity. Participants' attempt to cope with PPD through 4 stages—encountering terror, dying of self struggling to survive, and re- gaining control (Fig I).

In the first stage of PPD, encountering ter- ror, the women live with horrifying anxiet), relentless obsessive thinking, and envelojv ing fogginess. During the stage of dying of self they experienced alarming unrealness, isolation, and thoughts/attempts at self-harm. The third stage of PPD, struggling to sur- vive, reflects the women's attempts to sur- vive by praying for relief, battling the sys- tem, and seeking solace in support groups. In the final stage, regaining control, partici- pants experience unpredictable tmnsitioning, mourning of lost time, and guarded recovery. These 4 stages of PPD subsume the 11 themes

Stage 1

From Practice to Midrange Theory and Back Again

Stage 2 Stage 3 Stage 4

133

Horrifying anxieiy attacks

CONDITIONS CONSEQUENCES STRATEGIES

1. The 4-stage process of Teetering on the Edge.

CONSEQIENCES

generated in Beck's earlier phenomenological study,'̂ which, according to Beck,'"* extends and enhances the trustworthiness of her con- ceptualization of PPD.

Internal consistency

The major concepts in Beck's theory of PPD {loss of control, encountering terror, dy- ing of self struggling to surinve, and regain- ing control) are moderately abstract and rela- tively narrow in scope. All of the important concepts in Beck's theory are clearly iden- tified, as are the propositions that explicate the relationships among them. The author explains each of the concepts and supports them with direct quotes from participants. With respect to the concept of dying to self Beck furnishes'"*̂ '"*'** a partial audit trail illus- trating how she derived the concept from the data. The fact that the 11 themes from her phenomenologicai study'^ readily sub- sume into the codes in her grounded theory study'** indicates a high degree of transfer-

ability, dependability, and congruence of re- sults between the studies. Not only is infor- mation not lost, but the findings from a prior phenomenological study'^ are integrated into Beck's'^ ground theory research project. Tliis suggests a high degree of internal consis- tency and congruence among elements of the theory.

An assumption underlying Beck's theory is that PPD is a significant women s health prob- lem that not only affects individual women but also has deleterious effects on their chil- dren's health and development.*^"'" Despite the fact that PPD had received considerable research attention by 1993, little of it was qualitative in nature. That being the case. Beck believed that some aspects of tlie ex- perience of PPD remained underexplored. As well, because previous studies had never demonstrated an unequivocal link between PPD and the physiological changes associated with pregnancy and childbirth, there were un- doubtedly other factors at play (eg, psychoso- cial, environmental, etc).

134 ADVANCES IN NURSING SCIENCE/APRIL-JUNE 2005

Other assumptions supporting Beck's the- or>' of PPD are those embedded in the qual- itative inquiry paradigm, which is consistent with nursing's values. Participants in qualita- tive research are viewed as competent know- ers of their own experience and, as such, are collaborators in the inquiry process. In this tradition, there is emphasis on under- standing phenomena by attending closely to participants' lived experience. Furthermore, because qualitative research is discursive in nature and emergent in design, the researcher examines data for patterns of meaning with the aim of objectifying those patterns for sci- entific inquiry, while at the same time en- deavoring to remain true to the participants' construction of their experience. Qualitative research arises from traditions of human sci- ence inquiry in which the intent is to con- struct a holistic and ecological understanding of the phenomenon in question.

Empirical adequacy and testing The empirical adequacy of Beck's theory

of PPD becomes apparent in her subsequent work. She went on to develop the Postpartum Depression Predictors Inventor}'"' (PDPI), a tool to identify women at risk for develop- ing PPD. The PDPI is a checklist of 8 risk fac- tors, determined through 2 meta analyses^^- '̂ to relate to PPD. These factors include pre- natal depression, prenatal anxiety; history of previous depression, social support, marital satisfaction, life stress, childcare stress, and maternity blues. The PDFI is used in clin- ical settings across North America and in Iceland."*̂ In 2002, Beck published a revised version of the PDPI—the PDPI-R. which in- corjiorates the results of another, more recent meta-analysis.'̂

Beck has also collaborated with (lable' "̂ '"̂ ^ "* to develop the Postpartum Screening Scale (PDSS) for detection of PPD. The PDSS is a 35-item, Ukert-type, self-report instrument whose psychometric properties are supported in the literature and by content experts.'"^ Confirmatory factor analysis of the scale supports the existence of its 7 hypothesized dimensions. Analyses

of the 5-point response categories supported meaningful score interpretations and the internal reliability ranged from 0.83 to 0.94. Recently Beck'*̂ published a Spanish version of the PDSS.

Beck's research program clearly adopts a holistic approach to understanding the expe- rience of PPD. consistent with the perspec- tive and values of nursing. She explores views about women as w ĥole beings operating in the context of a person-health-environment- nursing complex. In all of her writing. Beck discusses the implications of the work for nursing care. At the same time, her work res- onates "with those in other clinicians and re- searchers who work in the area of PPD. We find evidence of this in the congruence be- tween Beck's theory with the work of Sichel and Driscoll (cited in reference 18) "earth- quake model" of PPD. Tlie latter explains that a woman's vulnerability to PPD reflects her unique genetic, hormonal, and reproductive makeup in the context of her life stressors. Depression, like an earthquake, can erupt when pressures increase at already highly stressed points of the system.

CONCLUSION

This article reviewed the basic elements of theory and chronicled the development of Teetering on the Edge. Cheryl Tatano Beck's theory of PPD." We argue that Beck's the- ory is an exemplar of substantive midrange nursing theory. Through ongoing refinement and testing of her theory of PPD, Beck has increased its generalizability across var- ious practice settings and continually iden- tifies new issues for investigation. Becks program of research on PPD represents a significant contribution to nursing practice knowledge tlirough midrange theory develojv ment, which, in turn, advances the discipline of nursing.

Midrange theory has the potential to ad- dress the theory-practice gap that continues to plague nursing and to develop the substan- tive practice knowledge needed to advance nursing as a discipline.

From Practice to Midrange Theory and Back Again 135

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